Waiver Wired: Nap Time?

Depending on what you read, Rusney Castillo could finally be close to joining the Red Sox. Shane Victorino has thrived while playing exclusively against left-handed pitching since coming off the disabled list, but he could really use a platoon partner. Daniel Nava and Jackie Bradley, Jr. aren't making much of a case right now, but Castillo has hit .304/.355/.449 with two home runs and six stolen bases across 17 games with Triple-A Pawtucket this season. He's been away from the team in recent days while on paternity leave, but he's expected back Thursday and I'm be on high-alert for a call-up to the big club. I hope you have him stashed already, as I recommended earlier this month.

Pittsburgh's Jung Ho Kang has been another popular stash in recent days and I went over his chances of fantasy success in this week's "Buy, Sell, or Hold" video.

MIXED LEAGUES

Wilin Rosario C/1B, Rockies (Yahoo: 34 percent owned)

Justin Morneau unfortunately landed on the 7-day disabled list last week due to a neck strain and concussion symptoms and it's unclear when he'll be ready to return. Given his history, it's understandable that the Rockies will be cautious. Rosario's catching days are over, so he has only received sporadic at-bats until now, but he figures to get most of the playing time at first base while Morneau is sidelined. The 26-year-old has plenty of pop and remains catcher-eligible, so he's an excellent pickup in most mixed formats right now, especially with the Rockies at home through the weekend.

Mike Napoli 1B, Red Sox (Yahoo: 40 percent owned)

Could Napoli finally be showing signs of life? The veteran slugger homered on Tuesday and now has back-to-back multi-hit games for the first time this season. I'll take it. He's still striking out more often than the league average and his BABIP sits at .211, so it's understandable that the batting average hasn't been there, but the good news is that he's healthy and his batted ball velocity has been among the best in the game so far this season. Per Tim Britton of the Providence Journal, Napoli recently looked at some video with teammate Dustin Pedroia to correct his hitting mechanics, so perhaps something has begun to click for him. Those who need some power should take a look.

Jimmy Nelson SP, Brewers (Yahoo: 23 percent owned)

Nelson owns a mediocre 3.73 ERA on the year, but aside from his clunker against the Reds on April 27, he's been quite good. The 25-year-old likely got some more believers after his performance on Tuesday when he held the Tigers -- one of the best offenses in the majors -- to just one run over eight innings, albeit with four walks. There are some interesting ingredients here. Nelson has the 15th-lowest contact rate among starters and the 13th-highest swinging strike rate as well as a ground ball rate above 50 percent. His ownership level deserves to be higher.

Curtis Granderson OF, Mets (Yahoo: 39 percent owned)

Granderson isn't the must-own that he used to be, but he's still doing things that warrant attention in fantasy leagues. While he's only hitting .245 so far this season, he owns a .347 on-base percentage out of the leadoff spot for the Mets and has scored 22 runs as a result. He's begun to show more power in recent days and is well within reach for another 20-homer season, especially with the friendlier dimensions in right-center at Citi Field and warmer weather on the way. It also wouldn't be a stretch to see him get to double-digit steals again. Again, these aren't sexy numbers, but it all adds up with counting stats.

Brad Miller 2B/SS, Mariners (Yahoo: 18 percent owned)

Hey, remember when everybody was pegging Miller as a breakout player last spring? I might have been part of that group. Things didn't work out as planned, as the 25-year-old hit just .225 with 10 home runs and a .653 OPS over 123 games and ultimately lost the starting shortstop gig to Chris Taylor. The Mariners are looking at Miller as a utility player these days, but he has made the most out of his playing time by batting .261/.323/.487 with 14 extra-base hits (including five home runs), 14 RBI, and three stolen base over his first 37 games this season. Four of his home runs came last week, for which he won AL Player of the Week honors. Fantasy owners will have to watch the lineup card carefully here, so Miller might be best utilized in daily formats, but he's capable of double-digit homers the rest of the way and should even steal a few bags. He's relevant as a MI (middle infielder) option.

Travis d'Arnaud C, Mets (Yahoo: 45 percent owned)

D'Arnaud was off to a great start this season before he suffered a fractured pinkie finger on his right hand when he was hit by a pitch on April 19. One month later, he's getting close to making his return. The 26-year-old resumed baseball activities early last week and began swinging a bat on Monday. He'll still have to go out on a minor league rehab assignment -- and the Mets will almost certainly want to see him catch a full nine innings before clearing him to return -- so chances are we won't see him until the start of June. However, what he did prior to the injury makes him worth stashing if you have a DL spot available.

Oswaldo Arcia OF, Twins (Yahoo: 26 percent owned)

While d'Arnaud is likely a week and a half away from returning from the disabled list, Arcia is on track to make it back sooner. The 24-year-old has been sidelined since May 3 with a right hip flexor strain, but Twins assistant general manager Rob Antony said Wednesday that he could begin a minor league rehab assignment this weekend with Triple-A Rochester. The 24-year-old was batting .276/.338/.379 with two home runs and eight RBI in 19 games prior to the injury and has big-time power upside, so he's another name worth waiting for if you have the roster flexibility.

Rubby De La Rosa SP, Diamondbacks (Yahoo: 22 percent owned)

De La Rosa is a pitcher who has been on the radar in the past, but he really hasn't been relevant in mixed leagues since 2011. That's quickly changing now that he's back in the National League. The hard-throwing 26-year-old has shown improved control this season while posting a 4.08 ERA and 47/12 K/BB ratio in 53 innings. He has walked three batters or fewer in all eight of his starts and has walked two or fewer batters in seven of them. His pitch mix hasn't really changed, but he's getting a bunch more whiffs on his slider than he did last season. The home run ball has hurt him at times, which shouldn't be ignored with his home ballpark, but he's an intriguing option in deeper formats.

Enrique Burgos RP, Diamondbacks (Yahoo: 13 percent owned)

With Addison Reed looking shaky, I recommended stashing Brad Ziegler last week. Hopefully you listened, as Reed is getting a break from the job and Ziegler looks like the best option to replace him, but Burgos has received the first two save chances and could also be in the mix. Of course, some of this has been a matter of circumstance. His save on Monday was in extra innings and Tuesday's was likely because Ziegler was unavailable after throwing 27 pitches over two innings the night before. Burgos' poor control is another reason to be skeptical about him having success in the role, but he throws really hard and has fanned 20 batters in just 11 2/3 innings so far this season. Grab who you can in this bullpen until there's some clarity.

Carlos Frias SP, Dodgers (Yahoo: 13 percent owned)

Frias was handed a tough-luck loss Tuesday against the Giants after tossing six innings of one-run ball, but he now owns a 2.55 ERA and 19/6 K/BB ratio across 24 2/3 innings of work this season. The 25-year-old has allowed three earned runs or fewer in all four of his starts. He averaged just 5.7 K/9 in the minors last season, so I'm not sure about the upside, but he throws pretty much everything hard and gets plenty of ground balls. I'll take my chances with him as a matchup play against the scuffling Padres this weekend.

Shopping at the five-and-dime:

(Players owned in under 10 percent of Yahoo leagues)

Shawn Tolleson RP, Rangers (Yahoo: 9 percent owned)

Rangers manager Jeff Banister pulled the struggling Neftali Feliz from the closer role over the weekend and said there were no defined roles in his bullpen, but Tolleson has quickly emerged as the pitcher to own here. The 27-year-old was warming up for a potential save chance on Sunday before it turned out he wasn't needed, but he finally notched his first major league save in Wednesday's win over the Red Sox. After posting a 2.76 ERA in 64 appearances with Texas last season, Tolleson has compiled a 3.44 ERA with 24 strikeouts and just four walks over 18 1/3 innings so far this season. Feliz could get another chance down the line and Keone Kela and Tanner Scheppers linger as alternatives, but Tolleson needs to be owned in more leagues right now.

Michael Taylor OF, Nationals (Yahoo: 3 percent owned)

The opportunity is there for Taylor, as Jayson Werth hit the disabled list this week with a left wrist contusion. No fracture or ligament damage was found in an MRI on Monday, but he's still dealing with quite a bit of soreness and needs some time to rest. Taylor has had some issues making contact in the majors thus far, which shouldn't be a big surprise if you've seen his strikeout totals in the minors, but there's some power and speed upside here too. He's an interesting short-term flier in deeper formats.

AL ONLY

Max Muncy 1B, Athletics (Yahoo: 0 percent owned)

With Ike Davis on the disabled list due to a Grade 2 strain in his left quad, Muncy and Mark Canha are expected to carry most of the load at first base during his absence. Muncy has made the most out of the opportunity thus far by safely in each of his last three games while amassing two home runs and two doubles. Don't expect the big power numbers to continue, but the 25-year-old has good plate discipline and could be a useful option in the short-term.

Ivan Nova SP, Yankees (Yahoo: 1 percent owned)

I'm guessing that Nova might already be stashed on the DL in some AL-only leagues, but he's a reminder in case he's still out there. The 28-year-old missed most of last season due to Tommy John surgery, but he's currently pitching in extended spring training games in preparation for a minor league rehab assignment. That could happen as soon as next week. The Yankees figure to use most of the 30-day rehab window to get him stretched out, so we are likely looking at a return in late-June. Command is often the last thing to return after surgery, which could be dangerous in the AL East, but those in league-only formats should be willing to take the gamble.

NL ONLY

Hector Olivera UTIL, Dodgers (Yahoo: N/A)

Olivera isn't listed on Yahoo yet, but that should change soon now that his $62.5 million deal with the Dodgers is finally official. The 30-year-old is currently working out at the team's spring training facility in Arizona in preparation to join High-A Rancho Cucamonga and should move up to Triple-A Oklahoma City shortly after that. Olivera was one of the best hitters in the Cuba and the Dodgers feel that he can make an impact in the majors very soon. It's hard to say where he'll fit, as the Dodgers already have quite a logjam at third base with Juan Uribe, Alex Guerrero, and Justin Turner, but he should be stashed on upside alone. This also goes for deeper mixed leagues and (obviously) keeper formats.

Tyler Moore 1B/OF, Nationals (Yahoo: 0 percent)

I wanted to mention Tsuyoshi Wada here, but he went out and fanned nine batters over 4 2/3 innings on Wednesday night against the Padres and is almost certainly gone in NL-only leagues. Thanks a lot, man. Anyway, here's another name in case he's off the board in your league. Michael Taylor has more fantasy appeal with me due to his power-speed combo, but don't ignore Moore as a possibility for at-bats while Jayson Werth is out with his wrist injury. Granted, the 28-year-old hasn't done much since a promising showing as a rookie in 2012, but he clearly has some pop. Look for him to get a handful of starts while Werth is on the shelf. He could run into a couple while doing so.