ST. LOUIS -- In the space of 1 1/3 innings, the Phillies did more damage to Kyle Lohse than the rest of the National League was able to manage in the previous four weeks.

Jayson Werth's two-run homer in the fourth put Philadelphia ahead, and Ryan Howard's grand slam in the fifth put the Phils on cruise control as Lohse and the Cardinals fell to a 6-1 defeat at Busch Stadium on Monday night. The Cardinals also lost center fielder Rick Ankiel to injury after Ankiel crashed into the left-center-field wall following a catch in the eighth inning.

The outburst against Lohse followed a third-inning plate appearance in which the pitcher was hit on his left elbow by a Joe Blanton pitch. Manager Tony La Russa speculated that being struck may have factored into Lohse's downfall. Lohse acknowledged that it was painful, but insisted that it shouldn't have affected his performance.

"I was pretty sore, but that's no excuse," Lohse said. "It's just one of those nights where I didn't have the best stuff. I got through it the first three innings, and then I left a couple balls right where the game plan was to not put those pitches, and that's what's going to happen when you make mistakes."

Lohse pitched an uneventful first three innings before the game started to get away from him in the fourth. He walked Chase Utley and Howard with two out in the first, but allowed only one other baserunner until Howard's fourth-inning single opened the barrage.

"I haven't looked at the film," Lohse said, "but [being hit] must have altered a little bit of my delivery."

Regardless of the cause, the difference was striking. Lohse took a 1-0 lead into the fourth, then allowed a Howard single and Werth's homer to begin that frame. In the fifth, Jimmy Rollins and Shane Victorino singled with one out, Lohse hit Utley and Howard hit a mammoth homer to right field to make it 6-1.

"The two innings that he pitched afterward, the quality of his stuff was not nearly the same," La Russa said. "That's just a fact, that he was different. I'm not trying to make an excuse."

It was easily the roughest start of the year for Lohse, who allowed almost as many earned runs in 4 1/3 innings on Monday (six) as in his previous five games combined (seven). He had not allowed a home run since his first start, on April 7. His ERA climbed from 1.97 to 3.22.

The right-hander has had a difficult sequence lately. He hurt his knee in a start at home on April 23. In his next start, on April 28 in Atlanta, he pitched despite a nasty stomach bug plaguing him all day long. And now the blow on the elbow, making it a hat trick of physical issues for the durable righty.

In the previous two games, though, Lohse was able to make it work. On Monday, the Phillies made him pay for his mistakes.

"I just didn't have the best command, and I made a couple mistakes in situations where you can't do that," he said. "Just one of those nights."

Joe Thurston drove in the Cardinals' only run, rapping a third-inning double that scored Lohse. Thurston had three hits, including two doubles, on the night.