The club's All-Star third baseman struggled again on Sunday afternoon as the Nationals wasted a strong pitching performance by Garrett Mock and lost, 2-1, to the Cardinals at Busch Stadium.
The Cardinals swept the Nationals out of town and opened up a 10-game lead in the National League Central, the biggest division lead in baseball. Washington dropped to 7-7 on the road since Aug. 2 and now needs a win on Monday night in San Diego to secure its first winning month since September 2007.
The Nationals seem to go as their star third baseman goes, which wasn't pretty in St. Louis. After going 5-for-10 with three extra-base hits and three walks when the Nationals took two of three from the Cubs at Wrigley Field, Zimmerman went 1-for-10 in three games against Cardinals pitching in the three losses.
The Nationals scored just seven runs in three games against the Cardinals after scoring 24 runs in three games against the Cubs.
"He's huge to us and he's done a great job," said interim manager Jim Riggleman. "When he's hitting the ball to right-center like that, we know good things are going to eventually happen. He's just missing by a tic."
Not helping Zimmerman and the offense was the Cardinals' dominant starting pitching. After facing future Hall of Famer John Smoltz on Friday night, the Nationals were stuck dealing with National League Cy Young Award hopeful Adam Wainwright.
The righty limited the Nationals' offense to one run on three hits in six innings. It was the 26th straight start that Wainwright pitched at least six innings and his 16 wins leads the Major Leagues.
Wainwright lowered his ERA to 2.47.
"It's not just good pitchers, it's good pitchers throwing good," Riggleman said. "These guys here -- Smoltz and Wainwright -- they had good days. When you face one of their top guys, you're hoping they don't have their best stuff. When the best guys have their best stuff, you're in trouble."
The Nationals got a quality start of their own from Mock. The righty went six strong innings, giving up two runs on four hits and struck out five.
After 13 relief appearances in April, Mock was moved into the starting rotation when he was recalled from Triple-A Syracuse on July 19 and has continued to improve each time out. He entered having won three of his past four starts.
"I just called Jim Riggleman and said, 'Whoever decided to put Mock in the rotation, it was a good decision,'" said Cardinals manager Tony La Russa. "Boy, he was very good."
While Mock may have been pleased with his overall outing, one at-bat in particular irked the Washington righty. With two outs and a runner on second base in the sixth inning and the game tied at 1, the rookie served up a 3-2 fastball to Albert Pujols that the star ripped up the middle for an RBI single.
That tiebreaking run was the last the Cardinals would score, but the damage was done.
"The pitch that's going to cost me some sleep tonight is the one that he got a hit on that scored the second run," Mock said. "I wasn't trying to throw the ball there, obviously -- not trying to throw the ball anywhere where he could hit it. I feel like I did do a good job of executing my pitches today, but that particular pitch, I've got to be better than that.
"When you're trying to throw a ball to arguably the best hitter in baseball, in that situation with a runner in scoring position with two outs, and you throw a pitch that he can hit, that's the type of stuff that makes me shave my head down further than it already is and just go crazy. I just can't stand it."
After the Cardinals scored an early run on a sacrifice fly to take the lead, Washington tied the game in the top of the sixth after Wainwright struck out Cristian Guzman and Zimmerman to start the inning. Adam Dunn and Josh Willingham both walked and Elijah Dukes' single to left scored Dunn to tie the game.
But up came the two-time MVP in the bottom of the sixth.
"It's tough to beat a team with a guy like that," Willie Harris said. "And then we ran across some tough pitching here. We faced a Hall of Famer and a possible Cy Young Winner. They shut us down."
B.J. Rains is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.