Tomko (2-2) went five innings, allowing five hits, a walk and a multitude of hard-hit balls. He ended the biggest threat against him by getting Alex Rodriguez to ground into a 1-2-3 double play with the bases loaded and one out in the third inning.
"He threw strikes, he stayed ahead of the hitters, he got an important double-play ball when he needed to," Girardi said of Tomko, who threw 52 strikes in 78 pitches. "That's the one thing; he didn't beat himself, and he's been like that. He's not going to make silly mistakes. He shut us down for five innings and it's frustrating, but you move on."
The double-play ball proved costly to the Yankees (74-35) - who lost a half-game to the idle Red Sox and lead the AL East by seven games - as the A's took advantage of one bad inning by A.J. Burnett to earn the victory and give Tomko the last laugh.
"It's been kind of a long road this year," he said. "It's had its ups and downs. But it was kind of ironic that my first start back up here was against my former team. It was a lot of fun. There were definitely some emotions kicking around before the game. Once we got into it, I kind of settled and it was a lot of fun.''
For Tomko, maybe, but definitely not for the Yankees' offense or Burnett (10-6), who allowed six hits and two walks in eight innings.
All three runs off him came in the fourth, an inning in which he balked home a run when he stopped his motion as he was about to deliver a pitch. Four of the hits off Burnett, who entered the game 5-1 after Yankees losses this season, came in the fourth.
Burnett was an out away from escaping the fourth down only 1-0, but the balk - which came one pitch after a vicious foul tip knocked off Jorge Posada's mask - and an RBI double by Mark Ellis on the next pitch produced a pair of two-out runs.
"He put the curveball down and I saw the sequence fastball in and it just kind of messed me up," Burnett said of Posada.
Burnett and Posada got their signs crossed in his previous start, Aug. 12 against the Blue Jays, mix-ups that resulted in three wild pitches. Burnett declined to discuss the wild pitches after that game and insisted Monday night that there are no sign issues between him and Posada.
"There's really nothing to correct," Burnett said. "We've been doing wonderful [all season]. It's two games in a row I've crossed him up, so I don't know whose fault it was tonight. I'm pretty sure it was mine."
The Yankees designated Tomko for assignment July 21 so they could make room on their roster for Sergio Mitre, who was to become their fifth starter, and released Tomko July 29. The A's signed him to a minor-league contract Aug. 5 and assigned him to Triple-A Sacramento, where he had no decisions and a 7.94 ERA in three starts before being called up Monday to start against the Yankees.
It was Tomko's first start since May 26 of last year, when he took the loss in the Royals' 7-2 loss to the Blue Jays.
With those credentials in tow, Tomko shut down his former team, one he criticized at the time of his designation for not giving him enough opportunities on the mound.
"I was pitching once every 10 days," said Tomko, who got his first victory as a starter since May 16 of last year. "That's not the easiest thing to do, so it's hard to stay fresh like that. But I think everything happens for a reason. And if the reason was to realize that I kind of wanted to start again, I think that's the most positive thing.''
Tomko's most critical inning was the third. Ramiro Peña - who played shortstop as Derek Jeter (three hits for the second straight game) got a day at designated hitter - singled to center. Jeter also singled, and Peña moved to third on Johnny Damon's long flyout.
Mark Teixeira walked to load the bases and bring up Rodriguez, who entered the game 4-for-8 with two homers and two doubles against Tomko. A-Rod, however, swung at the righty's first pitch, a slider away, and tapped it weakly back to the mound, starting a double play that was, well, as easy as 1-2-3.
"I'm looking to drive the ball, but you have to get a good pitch to hit,'' Rodriguez said, "and that pitch wasn't."
In the fourth, Rajai Davis ripped a one-out double to the gap in right-center, a drive that just eluded a diving Nick Swisher. With Kurt Suzuki at the plate, Davis recorded his 25th stolen base and scored on Suzuki's solid ground single up the middle to give the A's a 1-0 lead.
After a single by Scott Hairston - brother of the Yankees' Jerry Hairston Jr. - Ryan Sweeney's groundout put runners on second and third with two out. Then, with Ellis at the plate and Burnett pitching from the stretch, the righthander stopped in the middle of delivering a pitch, a balk so obvious that two umpires called it simultaneously. That made it 2-0, and Ellis doubled to right-center on Burnett's next pitch to make it 3-0.
That was the second "mental" mistake of the inning that bothered Burnett, with the balk, of course, being the first.
"It's the best I've felt with everything," said Burnett, who threw 99 pitches. "Strike one . . . everything. It was just upsetting. Two mental mistakes like that can cost you."
Tomko's night was finished after a called third strike on Damon ended the fifth inning. He punctuated it with a fist-pump, just as he had after A-Rod hit into the double play.
Tomko said there are no "ill feelings" toward the Yankees, but the victory clearly was meaningful.
"I expressed to Joe [Girardi] and [Brian Cashman] when I left that I don't think I got an opportunity right off the bat," Tomko said. "I wasn't mad about it, but I really wish I had the opportunity to be able to really show what I could do. I realized the situation. It's about winning there and they had horses that were doing well. Phil Coke and [Phil] Hughes and [Alfredo] Aceves, they were all pitching well. And they were going to go to those guys. I understood that. That's why I didn't have any bad feelings. I just feel like I didn't really ever get a chance to show what I could do.''
Three A's relievers took care of the Yankees after Tomko departed, allowing two hits and a walk in the final four innings.
The Yankees did put two runners on in the eighth against Brad Ziegler, as Jeter led off with an infield single and Rodriguez walked with two out, but Ziegler struck out Posada looking to end the inning. Andrew Bailey pitched a 1-2-3 ninth to pick up his 18th save.