Robertson threw about 20 pitches off a bullpen mound on Tuesday at Angel Stadium and completed the session encouraged that he will be able to come back from a stiff right elbow that sent him to Dr. James Andrews earlier this month for a checkup.
"Two weeks sitting out has been crazy," Robertson said. "I feel like if I can get ready and get a couple of outings under my belt, I'll be OK."
With the Yankees planning to carry only 10 pitchers for the first round of the postseason, Robertson's strikeout ability could be a valuable weapon.
Since his recall on May 26, Robertson has struck out 54 batters in 36 1/3 innings, spanning 37 appearances, and he's 2-1 with a 3.29 ERA in 42 appearances overall.
Yankees manager Joe Girardi said that Robertson is scheduled to throw two or three more side sessions before he would be able to get into a game, with the club hoping to use him during the final week of the season.
Robertson said that he threw mostly fastballs on Tuesday, mixing in some curveballs, and on Thursday he is expecting the intensity of his session to increase.
"I feel good," Robertson said. "Everything went well, with no problems. I'm looking forward to getting back out there."
Also on Tuesday, the Yankees welcomed left-handed reliever Phil Coke back to the club after a bout of acute gastritis that popped up during the club's flight from Seattle on Sunday and required a visit on Monday to the hospital, where Coke had two IVs administered.
Coke never made it from the team hotel to Angel Stadium on Monday, and Girardi said that he was expecting Coke to still be unavailable on Tuesday due to general weakness.
"I'm better than I was," Coke said. "It's over and done with. I'm looking forward to getting back on the field."
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.