He got his opportunity in his first game back in the majors with the Oakland Athletics.
Tomko pitched five scoreless innings to beat the Yankees less than a month after his release, winning his debut with the A's, 3-0 on Monday night.
"I wasn't mad about it but I really wished I would have had the opportunity to show what I could do," Tomko said. "I realize the situation. It's about winning there. They had horses that were doing well. I understood that. That's why I didn't have bad feelings. I just feel like I didn't really ever get the chance to show what I could do."
Three relievers finished the shutout, the fourth this season against the Yankees, who lead the majors in home runs and are second to the Los Angeles Angels in runs scored.
"It's frustrating to lose like that since A.J. pitched so well," Yankees manager Joe Girardi said. "He deserved better. Our starter goes eight innings and we get shut out. That's something you don't see every day. We're surprised we got shut out. We have a good offensive team."
Tomko (2-2) knows well how powerful the Yankees can be, having spent more than two months with the team earlier this season. But it comes as a bit of a surprise that he managed to silence his former teammates' bats.
The only real threat he faced came in the third inning when the Yankees loaded the bases with one out. But Tomko induced Alex Rodriguez to hit a comebacker and started a 1-2-3 double play that he punctuated with a fist pump.
"It was an exciting moment," Tomko said. "I'm usually not a big fist pumper. That could be the make or break play in the game."
Tomko allowed five hits and one walk before leaving after 78 pitches in his first start since May 26, 2008, for Kansas City. He got his only strikeout of the game against Johnny Damon to end his longest outing in the majors or minors since his last start.
Tomko started the season in the Yankees' organization and was called up to the majors in May. He went 1-2 with a 5.23 ERA in 15 relief appearances before being designated for assignment on July 21.
The A's signed him to a minor league deal earlier this month and he made three appearances in the minors before getting the start against his former team.
Oakland gave Tomko all the support he needed in the fourth inning. Rajai Davis started the rally with a one-out double and then stole third, his 25th steal of the season. Suzuki's single knocked in the first run. With runners on second and third and two outs, Burnett stopped his delivery in the middle for a balk.
"We got crossed up with the signs," Burnett said. "He wanted a fastball in and I thought I was throwing a curve away. When I saw him move it messed me up. There was no way I could throw that pitch."
Ellis' double knocked in the third run. That was all they managed against Burnett, who allowed six hits in his first complete game of the season.
Craig Breslow pitched two scoreless innings and Brad Ziegler struck out Jorge Posada with two runners on to end the eighth. Andrew Bailey pitched a perfect ninth for his 18th save, finishing Oakland's sixth shutout of the season.
"We didn't score and we didn't get enough hits," Damon said. "We hit a lot of balls hard but it went for naught on a night we get a great pitching performance from A.J. We needed to score some runs for him. It was one of those days where we were close but it didn't work out and only had the one bad inning."
New York had homered in 14 straight games, matching its longest streak since a 16-gamer in 1994. ... The day after breaking Luis Aparicio's all-time hits record for a shortstop, Derek Jeter started at DH for the Yankees. ... Yankees OF Nick Swisher doubled in the seventh inning and has reached base safely in 26 straight games. ... Athletics INF Bobby Crosby left the game with tightness in his left calf. ... Tomko's start ended a streak of 15 straight games started by an Oakland rookie.