No. 3 prospect Allen Webster instead drew the start on a day Farrell was expected to get a lot of relievers some work.
The season has already been a success for Lackey, considering how well he has pitched coming off Tommy John surgery.
"The fact that he's north of 100 innings this year coming off a year in which he didn't pitch, we felt like the extended rest right now would be beneficial for him," said Farrell.
Lackey's 10-13 record was not indicative of the way he pitched. He had a 3.52 ERA while pitching 189 1/3 innings and holding opponents to a .247 average.
"It goes back to the work he did in the offseason," said Farrell. "He set the foundation then with the way he reshaped his body, the way he got himself into condition and the work he's done between starts throughout the year. I don't know that we always look at years of pitchers returning from Tommy John, but this might be one of the more strong ones when you consider all the pitchers that have come back from the surgery.
"He's done a great job. The numbers, the win-loss is not indicative of the way he's pitched. We all recognize that, but I think right now, a well-deserved couple of extra days of rest."
Farrell will announce his American League Division Series rotation in the coming days. There's been considerable speculation that Lackey could start Game 2 at Fenway because of the drastic difference between his numbers at home (6-3, 2.47 ERA) and the road (4-10, 4.48 ERA).
Ian Browne is a reporter for MLB.com. Read his blog, Brownie Points, and follow him on Twitter @IanMBrowne. This story was not subject to the approval of Major League Baseball or its clubs.