KANSAS CITY -- Nick Swisher was issued a day off on Friday at Kauffman Stadium, one day after Yankees manager Joe Girardi thought he looked "exhausted" in the late innings of a 4-3 victory over the Royals.

Swisher said that he felt better once he got out of the game, chugged some Gatorade and took a dip in the clubhouse ice bath, but it was his 13-pitch at-bat against Kansas City lefty Bruce Chen in the fifth inning that gassed him. Swisher did not return to play the field in the eighth, but said he could play Friday if needed.

"I think that's why I'm the player and Skip is the manager," Swisher said. "It's easier that way. You show up and play when you play. If he throws you a day off, then you've got to know he's looking out for you and the team."

Girardi said that with the Yankees playing a fourth straight game in sweltering conditions -- the temperature in Kansas City leading up to game time was still flirting with triple digits -- he is considering resting each of his outfielders before the next homestand.

"What are you going to do?" Girardi said. "My guess is they're not going to cancel the game, so you've got to deal with it and watch your players a little closer."

The Yankees couldn't even catch a break from the summer heat during their commute on the highways. The club's bus had faulty air conditioning, so it was spewing hot air all the way during the 30-minute ride to Kauffman Stadium.

"That was the thing, we can't even roll down the windows," Swisher said. "You're like, 'OK, I'm in a sauna. Roll 'em up.'"

Extra rest prescribed for Pettitte after setback

KANSAS CITY -- Andy Pettitte suffered a setback on Friday as he pitched under simulated conditions at the Yankees' Minor League complex in Tampa, Fla., attempting to come back from a strained left groin that has sidelined him since July 19.

Pettitte was able to complete the full 50 pitches he had been scheduled to throw against hitters, but the veteran left-hander hesitated to use maximum effort, feeling as though he did not have full strength in his groin.

"It didn't go as well as we wanted," manager Joe Girardi said. "He felt like he could only push off 75 percent."

Pettitte is scheduled to meet the Yankees in Kansas City on Saturday, where he will be evaluated and rest for an extra couple of days. Pettitte had been hoping to pitch in a Minor League rehab game on Monday or Tuesday, but that will be pushed back.

"Part of it could be that he feels a little something and is afraid to let it go," Girardi said. said. "I think he did the right thing by not trying to push it. If he needs more time, then he needs more time."

At the time of Pettitte's injury, the Yankees had estimated that Pettitte would return in four to five weeks, which Pettitte had dismissed at the time as overly conservative. But with Friday's setback, that original time frame may prove accurate.

"He's frustrated, but would you expect Andy any other way?" Girardi said.

Second-round pick Gumbs signs with Yanks

KANSAS CITY -- The Yankees have agreed to terms with Angelo Gumbs, the club's second-round selection in the June First-Year Player Draft.

A shortstop and outfielder from Torrance (Calif.) High School, the 17-year-old Gumbs signed for $750,000, MLB.com has confirmed. The right-handed-hitting Gumbs was the 82nd overall selection in this year's Draft.

The Yankees have inked agreements with 14 of their top 25 picks this year, including first-round shortstop Cito Culver, who signed on June 18.

Worth noting

Alfredo Aceves pitched his second Minor League rehab game on Friday for Double-A Trenton vs. Harrisburg, hurling two hitless, scoreless innings with no walks and a strikeout. Aceves threw 26 pitches, 18 for strikes. ... CC Sabathia has pitched more than six innings and allowed three earned runs or fewer in each of his last 14 starts. According to the Elias Sports Bureau, it is the longest such streak by a Yankees pitcher since Ron Guidry did it for his first 15 starts in 1978. ... The Yankees have won 31 of 61 games (50.8 percent) when the opposing club has scored the game's first run, the most wins and best record in the Majors under such circumstances, according to Elias.