After all, he was pulled after just 4 1/3 innings despite having allowed just four hits and two runs against a high-powered Rangers offense at Tropicana Field.
But Shields insisted after the game that he wasn't angry, saying that he understood manager Joe Maddon's strategy of bringing in reliever Chad Qualls to face Michael Young with runners at the corners and one out.
"I felt like I gave up two hard hits the whole entire game," Shields said. "They had two nub hits here and there. But it's just what happens in the playoffs. Qualls is a ground-ball pitcher, and we needed a double play. So what are you going to do? It's Joe's decision."
It was a surprising move for all involved, but Maddon explained that he liked the matchup of a ground-ball pitcher against a player who grounded into 21 double plays, the ninth-highest total in the AL this year.
"It was a good situation for Chad," Maddon said. "He's a ground-ball pitcher. Young has hit into a lot of double plays this year."
But the decision clearly didn't work out in the Rays' favor, as Qualls caught a bad break when a check swing by Young that replays showed should have gone for a third strike was ruled a no-swing by first-base umpire Jerry Meals. Young quickly capitalized, delivering a three-run homer on the next pitch to put the Rangers up, 5-0.
Two of those runs were charged to Shields, and as a result, he ended with an unsightly line of four runs allowed over just 4 1/3 innings -- the shortest outing of his postseason career.
"Unfortunately, the end results of my numbers didn't really show how I pitched tonight," said Shields. "I felt like I pitched fine."
Shields, who posted a 5.18 ERA during the regular season, looked on Thursday much more like the "Big Game James" of the past, who posted a 2.88 ERA in four postseason starts during the Rays' memorable run to the World Series in 2008.
But luck simply wasn't on his side, as he allowed just two hard-hit balls -- a second-inning double to Nelson Cruz and a fourth-inning solo homer to Ian Kinsler -- but was saddled with the loss after the Rays managed just two hits in defeat.
There were traces of bad fortune nearly everywhere for Shields, as he twice plunked Rangers catcher Matt Treanor with errant changeups and allowed Treanor to score the first run of the game on a botched pickoff throw to first baseman Ben Zobrist with Elvis Andrus on first base in the third inning.
"I did a great job of keeping him right there," Shields said. "I think if Zobrist makes that catch right there or if I throw it closer to the bag, we get that out right there."
Instead the ball went off Zobrist's glove, allowing Treanor to score and Andrus to reach second base. But Shields was able to minimize the damage, getting Young to ground out and Josh Hamilton to fly out to end the inning.
But Shields ran into trouble again in the fifth inning, when he hit Treanor again to open the inning and allowed a one-out single to Andrus to put runners on the corners. But instead of working out of this jam, he made way for Qualls, and the rest is history thanks to Young's back-breaking three-run blast.
"I was disappointed," Shields said of being taken out early. "I'm a competitor. I wanted to go all nine innings, you know. I wanted the ball, and I felt Michael Young was 0-for-2 against me on the day with a strikeout and a ground ball. But Joe wanted to play the matchups, and he did. Unfortunately, it didn't work out."
Now the Rays find themselves in a 2-0 hole, and they have to win three in a row to reach the AL Championship Series for the second time in three years. But as Shields noted, the season's not over quite yet.
"The good news is, we're playing on Saturday," he said. "We're not going home yet. We have to fight our way through. They beat us two here, so we need to beat them two at their place. Hopefully we can get that Game 5 back here."
Rhett Bollinger is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.