Romero picked up another win on Monday against Tampa Bay, as he allowed three runs and six hits in six innings to improve to 13-9 to go along with a 2.84 earned run average.
"When everything's working it's easy to get through a game and go eight, nine innings," Romero said. "It's these outings that make you mentally strong and you're like, 'You know what, I grinded and I did everything I could and I made it through six.'"
Romero is 6-0 with a 2.11 ERA in his past eight starts, all of which have resulted in victories for Toronto. The native of California has eight consecutive quality starts and 21 in 27 outings this season.
His last loss, though, came at the hands of the Yankees back on July 16. He is 3-3 lifetime against them with a 4.80 ERA.
New York, meanwhile, will counter with right-hander Bartolo Colon, who has lost his last three starts and is winless in his past five outings. Colon pitched well in Baltimore on Sunday, but suffered the loss, as he allowed two runs and seven hits in 7 2/3 innings. He also struck out four without walking a batter. He is 8-9 on the year with a 3.63 ERA.
"It's real encouraging for us," manager Joe Girardi said. "He had struggled a little bit [recently]; he hadn't been as sharp. I thought he was real sharp today. I think that maybe the extra rest helped him recharge it a little bit and got him going."
Colon lost to the Blue Jays the last time he faced them and is 9-5 in 21 starts against them with a 4.02 ERA.
New York drew first blood in this set on Friday, as Ivan Nova shook off a pair of first-inning runs and held the Blue Jays scoreless over the next six frames and Brett Gardner's two-run homer and Robinson Cano's RBI single proved to be enough in the Yanks' 3-2 victory.
Nova (15-4) allowed just three hits and two walks en route to his eighth straight winning start and 11th consecutive positive decision.
"I know what I can do. I have to stay hungry and keep winning games," said Nova.
The Yankees have won five of their last six and jumped over the Red Sox for AL East supremacy, though it's a tenuous half-game advantage over Boston.
Brandon Morrow (9-10) gave up three runs on four hits over a six-inning start for Toronto, which came into the three-game series having won three of four.
The Yanks are 8-5 versus Toronto this season, including wins in five of the seven matchups in the Bronx.