Their actions alone were rather unremarkable, but served as indication of progress for both rehabbing right-handers, who continue to rapidly approach their respective healthy Bronx returns.
"Their biggest problem today was getting across the George Washington Bridge, like everybody else," Yankees manager Joe Torre said.
One day after pitching four innings for Double-A Trenton, Hughes tossed lightly on the field, while Karstens worked out in a bullpen session. Both pitchers will be back in action within days for Triple-A Scranton/Wilkes-Barre, and thoughts of big-league service have served as motivating factors for both players.
"I knew I could pitch at this level and compete at this level," Hughes said. "I think when you have that ultimate goal in mind, it's always easier to drive to something. It was tough at times, but when you have that to think ahead to, it made it easier.
"It's not going to do you any good to think about what happened. I just try to think about my next start, and it's finally good to be pitching again, no matter what level it is."
The 20-year-old Hughes suffered a strained left hamstring while working on a no-hitter May 1 at Texas, and was close to beginning a rehab stint when he sprained his left ankle in conditioning drills at Legends Field in Tampa, Fla., on May 25. That set him back to square one.
"I was so close to coming back from the hamstring," Hughes said. "I was throwing off the mound and everything was feeling good. I was excited about that, and then to [injure] the ankle when I did it, it was tough. It was kind of like starting all over again."
Karstens -- along with Hughes, one of seven rookies to make starts this season for the Yankees -- suffered a fractured right fibula when he was hit by a line drive in an April 28 start against the Red Sox.
The injury, coupled with right forearm tightness that cost the 24-year-old Karstens a chance at making the Yankees' Opening Day roster, continued a season that has ultimately tested Karstens' patience.
"It's been difficult, because the first three years that I played, I was never hurt," Karstens said. "I've just tried to take it in stride and stay positive about it. It's been tough, but I just had to keep my mind right."
Karstens said that during his rehab process -- which included a five-inning start on Tuesday for Trenton -- he drew upon the experiences of his 10 games (eight starts) for the Yankees over the last two seasons to help fuel his desire.
"Once you get a taste of it, you always want to taste it some more," Karstens said. "It's a lot different up here than down there. I was definitely motivated to come back."
Break 'em up: Posada has not started a game catching Mike Mussina since a May 22 loss at Boston, with Torre instead preferring to keep Mussina linked with backup catcher Wil Nieves. But with Nieves receiving Chien-Ming Wang in Thursday's afternoon affair, that string will end.
"Moose understands," Torre said. "If we're lucky enough to get to the postseason, that's the way it's going to have to be. They both understand and there has been no hesitation."
Order, order: The Yankees are leaning toward starting left-hander Kei Igawa in the first game of Saturday's doubleheader against the Devil Rays. The team would have to make a roster move to add right-hander Matt DeSalvo for the nightcap, so starting Igawa first would allow the Yankees to play the first game with an extra reliever on staff.
Statistically speaking: Jorge Posada has reached base safely in 92.3 percent of the games that he has started this year (72 of 78), the second-highest percentage among American League players, according to the Elias Sports Bureau. Only Kevin Youkilis of the Red Sox (92.6 percent, 75 of 81) has been more consistently on base.
Practice makes perfect: With a late report time for Thursday's afternoon game, pitching coach Ron Guidry took advantage of the emptier-than-usual clubhouse to practice his putting.
Guidry said he was tuning up for Torre's charity tournament later this month, smacking golf balls into small paper cups set apart by the length of the clubhouse. Guidry also hinted that this wasn't the first time he's made use of the facilities for his short game.
"You see, there's a ridge," he said, pointing toward a fold in the carpet. "You have to keep it right here."
At one point, a Yankees official spotted an errant cup and tossed it into the nearest trash bin. After a brief moment, the official realized he had changed Guidry's putting "green" and promptly returned the cup, as Guidry looked on in a sarcastic disbelief.
Coming up: The Yankees open a four-game weekend series with the Devil Rays on Friday, sending Mussina (4-6, 4.61 ERA) to the mound in hopes of improving to 8-0 in eight career starts against Tampa Bay at Yankee Stadium. The Rays counter with right-hander Edwin Jackson (1-9, 7.14 ERA), with first pitch set for 7:05 p.m. ET on My9.
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.