Here's a look at some of the more intriguing situations that unfolded during Boston's thrilling 7-5 victory that left the Angels one loss away from elimination.
Right on right
The situation: Right fielder Gary Matthews Jr., who has been managing a sore left knee for much of the season, went 0-for-3 and made an error in the Angels' Game 1 loss, and he's never faced Boston's Game 2 starter, right-hander Daisuke Matsuzaka.
The decision: Angels manager Mike Scioscia sat Matthews, a switch-hitter, in favor of Juan Rivera, a right-handed hitter with good pop who entered the game with a .333 career batting average in 18 ALDS games.
The outcome: Rivera went 0-for-2 with two walks and a run scored, but in one of the biggest at-bats of the game, Matsuzaka struck him out with two on, a run in and nobody out with the Angels trailing, 5-3.
The analysis: Given the Angels' offensive struggles in recent playoff losses to the Red Sox, it's hard to fault Scioscia for trying to give his lineup a spark. At the same time, it was an awfully public show of no-confidence for Matthews Jr.
The explanation: "Juan's a bat that we wanted to see match up [against Matsuzaka]. ... He's swung well in past playoff situations." -- Scioscia
Stand by your man
The situation: With two out in the top of the fourth inning, Angels starter Ervin Santana, who had allowed four runs and five consecutive hits in the first inning, gave up an RBI double to Jacoby Ellsbury that gave Boston a 5-1 lead.
The decision: Scioscia stuck with his All-Star righty.
The outcome: Santana got Dustin Pedroia to ground out to end the inning, ripped through a perfect fifth and got the first out in the sixth before Torii Hunter dropped Mark Kotsay's fly ball to center. Santana then allowed a single to Jason Varitek, and Jose Arredondo came on to load the bases with a walk before wiggling out of it.
The analysis: Santana had 23 decisions (16-7) during the regular season for a reason. He knows how to survive without his best stuff and still get deep into games. The primary options for Scioscia in the fourth were regular-season starters Jared Weaver and Jon Garland, neither of whom has pitched in relief in the playoffs, and lifting Santana at that point could have done more harm than good -- both in the game and inside Santana's head if he's needed to pitch Game 5.
The explanation: "I still liked the way Ervin was throwing the ball. It was that simple. He might have been a little too strong in that first inning, but he threw the ball real well after that." -- Scioscia
Save it for later
The situation: With Matsuzaka's pitch count approaching 100 after giving up a pair of walks to open the fifth inning, Hunter singled to left to cut Boston's lead to 5-3.
The decision: Francona stayed with Matsuzaka.
The outcome: Matsuzaka struck out Rivera, got Howie Kendrick on a fly ball to center and retired pinch-hitter Kendry Morales on a popup to keep the lead at two before calling it a night.
The analysis: Had a similar situation unfolded last season, Francona likely would have lifted Matsuzaka. By sticking with him, Francona rewarded his second-year righty with a chance to pitch out of his own jams and gave him a chance to complete the fifth and put himself in position for a win.
The explanation: "I tell you what, that was the ultimate tight rope. ... I said before the game that he doesn't give in, and he certainly didn't there." -- Francona
The situation: Red Sox up, switch-hitter Mark Teixeira and right-handed hitter Vladimir Guerrero due up to start the bottom of the seventh. Red Sox lefty Hideki Okajima had just worked a perfect sixth.
The decision: Francona, instead of playing the percentages and going with either of his right-handed setup men, Justin Masterson or Manny Delcarmen, stayed with Okajima.
The outcome: Teixeira and Guerrero both singled hard to left field, prompting Francona to belatedly replace Okajima with Masterson, who issued a one-out walk to load the bases and, one out later, walked Mike Napoli to make it a one-run game.
The analysis: Okajima held right-handed hitters to a .234 batting average in the regular season, and Guerrero was 0-for-4 against Okajima in his career, but the playoffs are a different animal. As was the case earlier in the game, Francona was trying to save his righties for later by squeezing a second inning out of Okajima, and it didn't pan out.
The explanation: "One of the reasons people like to play for Tito is because he shows a lot of faith in guys. You see examples of that all the time. You see it in every game." -- Red Sox outfielder Mark Kotsay
Mychael Urban is a national writer for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.