Over/Under: Rebounds for Heyward, Rios?

Jason Heyward was the star of MLB's '15 opener, collecting three hits and a SB for his new team,  the Cardinals - can Heyward revive his career in St. Louis -  O/U 39.5 combined HR+SB?

Brandon –  OVER. He went 27/21 in '12 as a (mostly) 22-year-old, and he's in St. Louis now, the NL's official rehabilitation center for post-hypers. At 25, with his talent, there should be plenty of great years ahead for Heyward, starting with '15. I'll say he finishes with 23 home runs and 18 stolen bases.

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Scott – OVER. You love that No. 2 batting slot in a deep St. Louis lineup, and anytime the Cardinals make a bet on a player, I want to backline the action.

Dalton – OVER. I went on record predicting Heyward would have 10 more homers/steals than Justin Upton this season, so I fully expect him to have a combo of 40-plus. The Cards plan to have an extremely aggressive approach on the base paths, and I'm buying into the organization's change in his swing.

J.D. Martinez hit the first MLB regular-season home run of '15. He hit 23 long balls for the Tigers in 123 games in '14 after washing out in Houston. Now a steady fixture in the middle of Detroit's lineup, how many home runs will he deliver this season - O/U 25.5 HRs?

Brandon –  UNDER. His HR/FB rate spiked last season when he finished with 23 home runs in 480 at-bats. And since he's not an extreme fly ball hitter, I would expect that his HR/FB rate will regress a bit back to his career average. Let's call it 24 home runs - close, but no cigar.

Scott – OVER. We have a tangible reason for the 2014 breakthrough, the mechanical overhaul, and Martinez has a delicious spot in the Detroit order, the No. 5 position. I love how Monday's blast was an opposite-field clout; if you want validation for a power hitter, look at the times he leaves the yard without pulling the ball.

Dalton – UNDER. I actually believe in Martinez's breakout last season, but it's tough to predict 26-plus homers for most hitters, let alone a 27-year-old who's yet to do so during his career. I expect him to be a very good hitter this year but to fall just short of this number.

Following much concern about his health this spring, Masahiro Tanaka took a loss in the Yankees' opener, allowing five runs in just 4.0 IP.  Will Tanaka be able to log more innings than his rookie campaign (136.1) and will his final ERA be O/U 3.399?

Brandon –  UNDER/OVER. Who wants to draft a pitcher with a slight UCL tear? And when that pitcher gets knocked around in the opener, doing so while obviously trying to avoid using his fastball, it doesn't do much to quell the dire thoughts that have surrounded him since late last season.

Dalton – UNDER and OVER. I entered the year very skeptical of Tanaka and his health situation. I don't want to overrate one start that came against a good offense, but his lack of FB velocity/usage didn't exactly help ease those concerns. I'm afraid Tommy John is inevitable (although to be totally fair, he produced a 14.6 SwStr%, so it's not crazy he can be effective with diminished velocity if he somehow avoids the knife).

Scott – UNDER and OVER is the only play here. Like many pundits, I wanted no part of Tanaka in the spring. He's pitching through an UCL tear and didn't want to work in the zone during Monday's opener. The baseball fan in me is certainly rooting for the story, but it's a smoke-fire situation.

Boston pitcher Clay Buchholz pitched seven shutout innings (with nine strikeouts) in Monday's opener. He's been all over the map the past couple years, sporting a 1.74 ERA in '13 and a 5.34 mark last season. Where will he land in '15  - O/U 3.499 ERA?

Brandon –  OVER. He's actually been under this number in three of the past five seasons, but his FIP has been over in four of those seasons. Fenway is a tough place to keep the ERA down, and among his AL East competitors, the Blue Jays, Orioles and Yankees project to be top 10 offenses - the environment is working against him.

Scott – OVER. If only the Phillies played in the AL East. If only Fenway Park offered a little cushion; some foul territory would be nice. I did add Buchholz in one mixer, but it's on a team where I'm in grave need of starting pitching – maybe the lineup will push him to some cheap wins. But I've been burned on this case many times in the past. The Buchholz Boogie usually results in a blowup.

Dalton – OVER. With his inconsistency while pitching in a park that's increased run scoring the second most of any in the American League over the past three years, this seems the safest bet. That said, Buchholz could easily win 15-plus games with Boston's offense on his side even if I'm right about this "over." There's some really nice fantasy potential here.

Last season in Texas, Alex Rios combined for just 21 HR+SB, his lowest tally since his rookie season in '04.  Now with Kansas City, Rios opened the year with a home run and a steal. Will Rios be able to resuscitate his once-potent power/speed game in KC - O/U 35.5 combined HR+SB?

Brandon –  OVER. He's only one season removed from stealing 42 bases and he's now playing for the team that led MLB in steals (and steal attempts) in '14. If he steals 25 bases, he only needs to add 11 home runs, a mark he eclipsed for eight straight seasons before last year. Age doesn't diminish talent at a uniform rate. I think Rios has a bounce-back season left in him.

Scott – UNDER, because I don't want to fully bet on the power, and Rios is at an age (34) where it's dangerous to chase the speed. Or maybe I'm just working through some of my Ned Yost angst (Mike Moustakas hitting second? Stop trolling us, #boomyosted).

Dalton – UNDER. Rios was a top-20 player in three of the previous four seasons before last year, when he somehow hit four homers over 492 at-bats despite playing in one of the better hitting parks in baseball. He recently hurt his thumb, an injury he says will affect him all season, and he now plays in a park that suppresses HR by RHB (although KC encourages SBs). I'm expecting way under here.

Atlanta traded star closer Craig Kimbrel just before its '15 opener and handed the closing reins to Jason Grilli, who saved 33 games for the Pirates in '13. Can Grilli, who picked up a save in Atlanta's first game, approach the success he enjoyed with Pittsburgh in '13 - O/U 27.5 saves?

Brandon –  OVER. Grilli was a pretty lights-out reliever from '11-'13 before going off the rails a bit last season. With his upper 90s fastball on display in his first save opportunity for Atlanta, I'd be williing to write last season off as a bad experience. I think Grilli will hold down the ninth for Atlanta for as long as they decide to keep him. And I wouldn't rule out the possibility that a trade deadline suitor looks to use him as a closer, as well. There were 20 closers with at least 20 saves by the All-Star break last season, so he has a good chance to get close to this number even before the likelihood of a trade.

Scott – UNDER. Mixed feelings on this one. Getting three outs in the ninth isn't that hard, and Grilli marked his territory nicely with the first conversion. But I still expect the Braves to win 75 games or fewer (no matter how good they've looked through two games), and if Grilli gets off to a strong push, it probably makes him a July trade candidate (which would probably cost him the closer baton). Might be a good time to shop Grilli to a save-needy opponent, lock in early profits.

Dalton – OVER. Atlanta should be among the lowest scoring teams in MLB, but Grilli looks locked into this role and plenty capable of capitalizing on it. I'd rank him as a top-22ish closer from here on out. His velocity was strong during his save against the Marlins (when he sent down the team's 3-4-5 hitters in succession).