ST. LOUIS -- After two subpar starts, Jeff Suppan was dominant Saturday night.
"That's the Jeff that cranked out so many of those games last year," manager Tony La Russa said. "He just looked like himself. He was really aggressive and had good stuff."
Yadier Molina had a two-run homer for the Cardinals, who will try to complete a perfect six-game homestand on Sunday. The NL Central leaders are 32-16, the second-best start in franchise history.
Nick Johnson's bases-loaded walk in the sixth drove in the lone run for the Nationals, who will be trying to avoid consecutive road sweeps in the series finale. At 24-25, Washington is below .500 for the first time since it was 3-4 on April 11.
"Our offense is still missing in action," manager Frank Robinson said. "Whoever goes out there against us looks like Cy Young."
Jason Isringhausen, the Cardinals' third pitcher, worked the ninth for his 14th save in 14 chances.
Coming off losses in his previous two outings, Suppan (4-5) didn't allow a hit until Brad Wilkerson's broken-bat single at the end of a 10-pitch at-bat with one out in the sixth. That turned out to be his only difficult inning, due to a couple more soft hits.
Marlon Byrd followed with a broken-bat infield single and Jose Guillen's dribbler down the third-base line stopped just fair to load the bases for Johnson, who fouled off two full-count pitches before walking to cut the deficit to 3-1.
Suppan escaped further damage when the next batter, Vinny Castilla, grounded into an inning-ending double play. Second baseman Mark Grudzielanek held his ground when Johnson barreled into him, making a strong relay.
"Johnson was all over him," La Russa said. "That's a double play that not many second basemen have turned."
Suppan said his location was a lot better than his two previous outings, when he allowed eight earned runs in eight innings.
"You have to have a short-term memory and really just go out there game by game," Suppan said. "What happened in the past is in the past. I'm just trying to keep it simple and make pitches."
Edmonds had been in a 1-for-14 slump before homering, hitting two doubles and driving in four runs on Friday night. He hit his ninth homer off Esteban Loaiza (1-4) to straightaway center leading off a three-run second.
Grudzielanek singled with one out and scored on Molina's second homer, both in the last in 10 days, to make it 3-0. Since a 1-for-31 start as the Cardinals' new catcher, Molina has batted .318 (34-for-107) to raise his average to .254.
Loaiza lasted six innings and gave up three runs and eight hits with six strikeouts and a walk, again suffering from lack of support. Entering the game, the Nationals had been scoring a major league-low 1.9 runs per nine innings in his starts, according to Stats, Inc.
"What can I do? I'm a pitcher," Loaiza said. "I just try to do the best job possible. I haven't gotten that much run support from my teammates, but I know they're out there battling 110 percent."
Edmonds is the third player to hit 100 homers at Busch Stadium, joining Ray Lankford (123) and Mark McGwire (119). ... Cardinals RF Larry Walker left after four innings with a slightly sprained left ankle. So Taguchi replaced him. La Russa said he hoped Walker would be available to pinch hit on Sunday. ... The Cardinals have won six in a row at home. ... Albert Pujols hasn't homered in eight games, his longest drought of the season. ... Guillen has eight hits in his last 19 at-bats. ... Brian Schneider is in a 4-for-37 slump. ... The 1941 team has the best start in Cardinals history, going 34-14 through 48 games.