The 24-year-old Tillman is 2-1 with a 2.70 ERA in three starts since being recalled from Double-A Bowie on July 16. He also allowed only two runs (zero earned) over 8 2/3 innings against the Mariners on July 4.
But Tillman has yet to pitch against a team with a dominating offense. That will change Tuesday night when he takes the hill for the Orioles against the American League East-leading Yankees in the Bronx. Tillman's three wins this season have come against Seattle, Cleveland and Tampa Bay.
In his last outing, against the Rays, Tillman allowed two runs on five hits over six innings, while striking out five and walking four. He has won back-to-back outings for the first time in his four-year career.
"Tilly's a tough guy," Orioles manager Buck Showalter said. "He competes. There's a lot of things to like about him. And I think, hopefully, he's starting to grasp that."
The Yankees will counter with young right-hander Ivan Nova. Nova has been solid for New York all season, but he hasn't won since July 8. He allowed only two runs on two hits over five innings in his last outing, against the Mariners, but he took a no-decision in the Yankees' 5-2 win.
Nova struggled with his command in the start as he walked a season-high six batters.
"I didn't really have my fastball command today," Nova said afterward. "I fell behind the hitters the whole game. Six walks; it wasn't a good day for me."
Nova is 10-4 with a 4.08 ERA in 20 starts this season, and he has allowed three or fewer runs in 10 of his last 11 outings dating back to June 6.
Orioles: Andino could return for Tuesday's game
Second baseman Robert Andino could return to the team Tuesday if all goes well in his rehab game with Triple-A Norfolk on Monday night. Andino has been on the disabled list since July 17 with a left shoulder strain. He was originally expected to miss three to four weeks, but he has progressed quickly.
Andino played for Norfolk on Sunday with good reports.
"[Triple-A manager Ron Johnson] asked him about coming out of the game about the seventh, eighth inning, [and] he said, 'No, I'm fine,'" Showalter said. "[They] said he played well, moved around well."
Andino was hitting .230 with five home runs and 21 RBIs in 79 games before heading to the DL.
Designated hitter Jim Thome is schedule to have an MRI for neck spasms at 11 a.m. ET Tuesday in Baltimore. Thome tried to hit before Monday's game, but the pain hadn't subsided the way he thought it would.
Yankees: Swisher to remain at DH for time being
Nick Swisher started at designated hitter for the second straight day on Monday, and manager Joe Girardi said he could remain there for the next few days. Swisher hasn't started in the outfield since mildly straining his hip flexor on July 20.
"Right now, with the way everything is going, we can afford to do this," said Swisher, who has gone 3-for-8 with four strikeouts in the two starts at DH. "I guess that's kind of the answer. Why wouldn't we? As soon as we get back on the field playing, you don't want to leave for the rest of the time."
Girardi said the addition of Ichiro Suzuki has made it easier to use Swisher at DH. Suzuki has started in right during Swisher's absence, with Andruw Jones or Raul Ibanez in left.
Nova is 3-1 with a 4.50 ERA in seven career starts against the Orioles.
Tillman is 1-3 with an 8.71 ERA in five career starts against the Yankees.
Suzuki homered for the first time as a Yankee when he hit a solo shot in the seventh inning of Monday's 5-4 loss to the Orioles. It was his fifth home run overall this season, and the 100th of his Major League career.