"I was looking for that pitch, and he left it up and I just hit it hard," Wells said.
The pitch Wells was looking for was a changeup, which Giants left-hander Noah Lowry delivered to open the inning.
Wells' offensive effort gave the Cardinals a 2-0 lead going into the fifth, but two errors and a triple from the Giants' Ryan Klesko tied the game. The errors were charged to second baseman Aaron Miles and Albert Pujols, who made a rare drop on a throw from second.
"We didn't play great defensively, but [Wells] pitched around most of it," manager Tony La Russa said.
Wells also scored the first run for the Cardinals in the third inning when he reached second with a base hit and a throwing error from the Giants. Another throwing error on a sacrifice bunt laid down by David Eckstein brought Wells home. A sliding catch from Giants right fielder Randy Winn ended the third with two Cardinals left on base.
In addition to contributing the Cardinals' only two runs, Wells pitched to the minimum number of batters in the first four innings.
Wells threw a total of six innings, allowing five runs (four earned) on six hits.
Those game stats looked better before the sixth inning, when Wells walked two and allowed three runs on three hits. For the first time, Wells started missing pitches and falling behind in the count, and the Giants took advantage.
"If you're too stingy, like at times I was today, and you miss off the plate or off the corner and then you fall behind," Wells said.
Two of the Giants' three six-inning runs were hammered in off a double from Rich Aurilia. Aurilia has a .429 batting average and a .786 slugging percentage against Wells.
"As the intensity picked up, I didn't execute as many of the pitches as I would like, and they did a good job of taking advantage of pitches that were in the middle of the plate," Wells said.
But it's hard to fault Wells for one bad inning when he was the only player producing offense. The Cardinals collected five hits, but Wells was the only runner to make it past second.
"It's not the best way to play, so I think it's safe to say we're concerned," La Russa said.
The Cardinals went 0-2 in San Francisco and now hit the road for a three-game series in Chicago, where Miles is confident the Cardinals will change their luck.
"These things tend to go in streaks," Miles said. "But we'll work it out. We've got so many All-Stars on this team."