Pettitte was scheduled to start on Sunday against the Baltimore Orioles, but is now aiming to start sometime early next week, possibly Tuesday or Wednesday against the Arizona Diamondbacks, per Ehalt's report.
New York will conclude its current series with Baltimore on Sunday and have an off day on Monday before beginning a three-game home series against Arizona on Tuesday night.
The Yankees aren't taking any risks with Pettitte, who has pitched more than 3,100 innings since 1995 and is set to turn 41 this June. Plus, with New York just a half-game out of the AL East lead coming into Friday, there's no rush for Pettitte to return to the lineup.
The 40-year-old went 5-4 in 12 starts last season, recording 69 strikeouts and sporting a 2.87 ERA in a little over 75 innings pitched. Pettitte is in his 15th season with the Yankees and boasts a career win-loss record of 247-142, which includes three seasons with the Houston Astros from 2004 to 2006.
Following an alarming 1-4 start to the season, the Yankees are sitting comfortably at 4-4 having won three straight coming into Friday's showdown with the Orioles.
Follow Bleacher Report Featured Columnist Patrick Clarke on Twitter.