1. Stick with ace Chris Sale, who had achieved the rare combination of being both overpowering and strikingly efficient.
2. Go to closer Craig Kimbrel, who was untouched in his three previous outings (eight strikeouts, no baserunners over three innings) and had two days of rest coming into Thursday.
Farrell chose the latter, which initially led to heartbreak. Kendrys Morales belted Kimbrel's second pitch, a 96.8-mph heater, over the wall in center to tie the game.
This robbed Sale of a win on a day in which he threw 80 of his 102 pitches for strikes, a career-high percentage of 78 percent for the lanky lefty. Over eight innings, Sale allowed four hits and a walk while punching out 13.
"I'm going to want the ball in that situation 10 times out of nine. It is what it is. Do I want to? Yeah. But at the end of the day, he's the manager and makes the calls," said Sale. "Check the book. Craig's been pretty [darn] good back there. We ended up winning."
Yes, the Red Sox made things right in the end, and provided an easier night of sleep for Farrell with that three-run rally in the 10th led by a bases-clearing double by Mookie Betts.
"It was a tough decision, but one where, we take the lead, we've got Craig Kimbrel, who's thrown the baseball extremely well, he's been dominant in his own right," said Farrell. "He's well-rested. After kind of a long inning when we get a challenge review and we score that run late in the inning, we felt it was time to turn it over to a guy that was fresh and powerful. Unfortunately, the second pitch goes out of the ballpark."
Give credit to Kimbrel, who sat down the next six batters he faced for the win -- five of them on strikeouts.
"I didn't want to lose the game," said Kimbrel. "I still had a job to do. [Pitching coach] Carl [Willis] came through and told me if we scored some runs, I was going back out. Initially, there's just that frustration. I gave up the game. I felt like it was my job to keep the game close and keep it going."
Would Farrell have gone back to Sale in the ninth if the Red Sox hadn't jumped in front?
From the sound of it, if the Red Sox had gone down 1-2-3, Sale would have pitched the bottom of the ninth. But the way things unfolded, with an extended rally that included a review of nearly two minutes on the go-ahead single by Xander Bogaerts, it became Kimbrel Time in Farrell's mind.
"That's certainly an option," Farrell said, when asked if what would have happened if the game remained scoreless. "Again, Craig is throwing the ball so well and so dominant, so that was the decision."
And despite Sale's no-decision, he has been amazing in his first four starts with the Red Sox, going 1-1 with a 0.91 ERA. The Red Sox are 3-1 in those games. Thursday was his best so far for Boston.
"He was outstanding, powerful, a lot of strikes," said Farrell. "It was something unheard of, nearly 80 percent strikes on the day. All three pitches were working. He had such good swing-and-miss to his fastball up and away, up to his arm side against right-handers."
Ian Browne has covered the Red Sox for MLB.com since 2002. Follow him on Twitter @IanMBrowne and Facebook. This story was not subject to the approval of Major League Baseball or its clubs.