Kyle Busch wins as Joey Logano crashes with Denny Hamlin on last lap and scuffles with Tony Stewart

A crash on the final lap of Sunday's Auto Club 400 between Denny Hamlin and Joey Logano sent Hamlin to the hospital, left Logano fuming, validated a rivalry that started boiling last week at Bristol and gave Kyle Busch, teammate of Hamlin and former teammate of Logano the win.

And in a separate incident, Logano left Fontana with another nemesis as Tony Stewart confronted him, pushing and swinging after the race because of a move that Logano made while the two were battling for the lead on the race's final restart with 11 laps to go.

After that restart, which we'll get to briefly, Logano took the lead from Busch, who led the race's most laps. Over the final five laps, Hamlin closed in on Logano, and as the two approached the white flag, Hamlin pulled up to Logano's back bumper and then alongside him as the two entered turn one.

[Related: Kyle Busch caps off weekend sweep at Fontana]

The two stayed even through turns one and two and down the backstretch, with Hamlin to the outside and Logano to the inside. They were in the same formation entering turn three, with Logano hugging the white line and Hamlin just to his outside, tucked as tight as possible to the right side of Logano's car. As the two went through turns 3 and 4, Logano wasn't giving an inch. His car washed up the track a bit and Hamlin held his line. The two bounced off each other before Logano's car hit the outside wall and Hamlin's went spinning toward the inside. Meanwhile Busch, who was at one time a seemingly distant third, breezed by on the outside of the track to take the checkered flag.

"He probably shouldn't have done what he did last week, so that's what he gets," Logano said, likely not knowing the impact that Hamlin's car made with the inside wall.

The impact Hamlin made with the inside wall was so hard that it lifted the rear tires of his car off the ground, and shot it into a spin. Hamlin climbed from his car under his own power, but was then treated by track officials on the ground next to his car before he was airlifted to a nearby hospital. NASCAR officials said that Hamlin was awake and alert in the infield care center before he was sent by helicopter to the hospital because of traffic congestion. (Update from Joe Gibbs Racing, which released the following statement Sunday night: "Hamlin complained of lower back pain at the track’s infield medical center and was transported to a local hospital for further evaluation. Hamlin will remain at the hospital overnight for observation.")

Let's flash back to a week ago for a moment. At Bristol, Hamlin got into the back of Logano as the two were battling for position at the front of the pack and the contact spun Logano into the wall. Logano was furious, and after the race, promised payback against Hamlin. Hamlin said that the contact was purposeful, though he didn't mean to wreck him. And that promised revenge? It wasn't going to be an issue because Hamlin usually wasn't in the same part of the field as Logano. (Remarks that he apologized for on Friday.)

This was Logano's opportunity. He hadn't been around Hamlin for most of the day, but that was because he was in front of him. Now they were sharing the same track space, with Hamlin on tires that were some 20 laps fresher than his. It was, in essence, the time to live up to the "Sliced Bread" nickname that Mark Martin had bestowed on him as a teenager and show Hamlin that he wasn't messing around.

After the race, it was apparent Stewart wasn't either, and this week he was the one professing revenge, vowing payback on Logano after that restart, when Logano protected the white line with Stewart behind him in third as the field hurtled toward turn one.

"What the hell do you think I was mad about?" Stewart said after the race. "Dumb little [expletive] runs us clear down to the infield. He wants to [expletive] about everybody else. He's the one who drives like a [expletive]. I'm going to bust his ass.'"

Stewart added later: "He's nothing but a little rich kid who has never had to work in his life."

The 2011 champion has almost made himself the de facto NASCAR police chief when it comes to blocking and aggressive defensive driving (nevermind his block last year at Talladega caused a massive pileup that saw his car upside down), and he was livid with Logano's defense of the low line on that restart with 11 laps to go. Stewart parked his car alongside Logano's on pit road after the race and shoved Logano and failed to connect on a couple swipes as crew members pulled the two drivers away.

"Tony was just upset about a restart that I was racing him really hard on the bottom trying to make sure I protected my spot" Logano said. "What I was doing actually was I was racing the 18 on the restart and he was spinning his tires. The rule is you can’t beat him to the start finish line so I am pedaling it which gave Tony the run to go underneath me. I wanted to block that because I knew if he put me three-wide that would be the end of my race and I wouldn’t win. I was smart enough to realize that. Then I had to just do what I had to do to get to the front and try to win the race.”

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