Yankees 2, White Sox 1

Ivan Nova attracted headlines for all the right reasons this time.

He set aside any worries he had about a Major League Baseball investigation and earned his first career win, Marcus Thames hit another homer and the New York Yankees beat the Chicago White Sox 2-1 on Sunday.

It was an impressive outing for Nova (1-0), who allowed one run and five hits with seven strikeouts and one walk in 5 2-3 innings.

''(We're) asking a young man to step up and that's exactly what he's doing,'' manager Joe Girardi said.

He outpitched Gavin Floyd (9-11) in his second start, a day after reports surfaced that the league is investigating him and a former minor league teammate for allegedly injecting each other with B-12 shots.

The vitamin is not on baseball's list of banned substances.

MLB is focused on the issue of whether Nova and pitcher Wilkin De La Rosa injected each other last season at Double-A Trenton and wants to make certain the shots were in fact B-12. The New York Post first reported the story.

Nova wouldn't discuss the investigation, although he did say ''it's nice'' to get the win after the reports the previous day.

He said he spoke to relatives on Saturday, and they told him to relax, to ''pitch like I was in Triple-A.''

''I said, 'OK,''' Nova said.

Then, he followed their advice.

''He's a tough guy. He's always been the same way, he's relaxed,'' catcher Francisco Cervelli said.

Thames led off the second with his fifth homer in five games and ninth overall, and Brett Gardner singled in a run in the third to make it 2-0. Cervelli chipped in with a career-high four hits and the Yankees hung on to take two of three from the White Sox.

The loss was the ninth in 14 games for Chicago, which retired Frank Thomas' number and then wasted a solid effort by Floyd.

Ozzie Guillen also got ejected for the fifth time this season by first base umpire Bob Davidson in the ninth for calling Brett Gardner safe on what the manager thought should have been a double play.

''I was tired of seeing that all weekend,'' Guillen said.

The losses are getting tiresome, too.

''We know what time it is,'' Gordon Beckham said. ''September is around the corner and we have to make a push.''

They got an RBI single from Juan Pierre in the fifth but left the bases loaded in the sixth.

Nova left with a runner on first and two outs after retiring Andruw Jones on a fly to center, and things got real interesting after that.

Former White Sox pitcher Boone Logan came in, and A.J. Pierzynski reached on a slow roller down the third base line that was ruled a hit after the throw from Eduardo Nunez pulled Nick Swisher off the bag.

Kerry Wood then threw a wild pitch to Alexei Ramirez and walked him to load the bases before Mark Teahen grounded out to end the threat.

Joba Chamberlain allowed one hit over 1 1-3 scoreless innings. Mariano Rivera worked the ninth for his 27th save in 29 chances, walking Gordon Beckham with one out before Pierre forced him and Omar Vizquel fouled to the catcher.

Floyd allowed two runs and seven hits over 6 2-3 innings. He left after giving up a two-out walk to Nunez and single by Cervelli, before Chris Sale struck out Gardner.

The Yankees threatened to add to their lead in the eighth but came away empty-handed when Bobby Jenks retired Austin Kearns on a force with the bases loaded.

Thames, who went deep twice on Saturday, started the second by driving a 2-2 pitch from Floyd beyond the left-field bullpen.

''I'm a power guy,'' Thames said. ''And it's big for power guys - you have to get into a rhythm to get some stuff going. But I know my role, so I don't need to start putting pressure on myself. I'm just glad if I hit the ball hard every time I get a chance.''

NOTES: A fan seated near the first-base dugout got struck in the head by a line-drive foul by New York's Curtis Granderson leading off the seventh. He was tended to for several minutes before walking away, still apparently woozy, holding a bandage. The White Sox had no further information afterward. ... Yankees 1B Mark Teixeira is day to day after he was scratched from the lineup because of a bruised right thumb. He hurt it making a diving stop on Friday and left Saturday's game after two innings. He said it was ''maybe a little better but not much.'' ... Lance Berkman, out with a sprained right ankle, was headed to Double-A Trenton for two rehab games starting Monday.