Cardinals 4, Nationals 1: Yadier Molina ripped a go-ahead two-run single and rookie Shelby Miller tossed six solid innings as host St. Louis completed a three-game sweep to inch closer to seizing the National League Central title.

Matt Adams homered and scored twice for the Cardinals, who reduced their magic number to one and moved three games ahead of second-place Pittsburgh. St. Louis, which has won seven of its last nine, wraps up its regular-season slate by beginning a three-game series against the visiting Chicago Cubs on Friday.

Bryce Harper slapped an RBI single in the first inning, but that was all Washington could muster as Jordan Zimmermann (19-9) was thwarted in his bid to become the NL's first 20-game winner.

With the game tied at 1-1 in the fourth inning, Molina continued his hot hitting by depositing a 2-1 fastball from Zimmermann into center to plate Matt Holliday and Adams. Molina, who finished 1-for-3, is 7-for-15 with one homer and five RBIs in his last four home games.

Miller (15-9), who allowed one run on four hits, improved to 3-0 in his last four turns and registered his 13th quality start of the season. Three relievers bridged the gap to Trevor Rosenthal, who retired the side in the ninth for his third save.

GAME NOTEBOOK: Zimmermann was looking to join Gio Gonzalez (2012) and Ross Grimsley (1978 with Montreal) as the only 20-game winners in franchise history. The 27-year-old Zimmermann fell to 4-1 in September after permitting four runs on six hits in seven innings. ... St. Louis, which won all six meetings against Washington, completed a season sweep of at least six games for the first time since claiming all seven matchups versus the Los Angeles Dodgers in 2006. ... The Nationals wrap up their season on the road by opening a three-game set against Arizona on Friday.