ST. LOUIS -- St. Louis is apparently bent on entering the National League playoffs with momentum on its side.
Rookie right-hander Shelby Miller pitched into the seventh inning for his 15th win as the Cardinals capped a three-game sweep of Washington on Wednesday with a 4-1 victory at Busch Stadium.
St. Louis (94-65) reduced its magic number for clinching the NL Central to two and eliminated Cincinnati, a 1-0 loser to the New York Mets, from division title consideration. It leads Pittsburgh by 2 1/2 games, pending the outcome of the Pirates' game at the Chicago Cubs.
Miller (15-9) overcame a shaky first inning, which saw him allow two walks and Bryce Harper's looping single to left for the Nationals' only run, to work six solid innings. He yielded only hits and one run, fanning three and walking three as the Cardinals won for the eighth time in 11 games.
Washington's Jordan Zimmerman (19-9) was denied his 20th victory despite allowing six hits in seven walk-free innings. He gave up four runs and struck out two as the Nationals (84-75) were swept 6-0 in the season series.
After Matt Carpenter's groundout to first scored Daniel Descalso with the tying run in the bottom of the third, St. Louis took the lead for good in the fourth.
Matt Holliday was hit by a pitch to start the inning and moved to third on Matt Adams' double. Yadier Molina's single up the middle brought both runners home for a 3-1 lead.
Adams finished the scoring in the sixth with his 17th homer -- his eighth in the last three weeks since replacing injured Allen Craig on an everyday basis at first base.
Four Cardinals relievers picked up the last nine outs, with Trevor Rosenthal mowing through Washington 1-2-3 in the ninth for his third save in as many games since replacing slumping Edward Mujica as the closer.
NOTES: Holliday (back tightness) returned to the lineup after a three-game absence and batted in the third spot. ... Washington has an day off on Thursday before starting a season-ending three-game series Friday night in Arizona. It will send Stephen Strasburg to the mound against Patrick Corbin. ... The Cardinals also get Thursday off before welcoming the Chicago Cubs to town for their last regular-season series. In Friday night's opener, Lance Lynn will look for his 15th win against Travis Wood.