KANSAS CITY, Mo. -- The St. Louis Cardinals are headed in the right direction, and the Kansas City Royals are turned around in the wrong direction.

Yadier Molina and Jedd Gyorko each homered and drove in three runs as the Cardinals routed the Royals 10-3 on Tuesday night.

St. Louis (57-56) won its fourth straight to boost its record above .500 for the first time since June 1.

"It's better than being under .500," said first baseman Matt Carpenter, who had two of the Cardinals' 14 hits. "We've been there for a while. Now we can kind of get on a roll."

The Royals (57-55) have lost seven of nine to fall four games behind the Cleveland Indians in the American League Central.

"When things aren't going good, you're not getting breaks, and that's part of the reason why you're not going good," Kansas City manager Ned Yost said. "We're definitely not getting breaks. We're not really making our own breaks either."

Molina homered leading off the fourth and contributed a two-run single in a six-run fifth. Gyorko capped off the big inning with a three-run shot.

"I think he's in a pretty good place right now, a good opportunity for him to take off with it," Cardinals manager Mike Matheny said of Gyorko.

Randal Grichuk led off the fifth with a home run for the Cardinals, who have scored 34 runs in their past three games.

"Right now it's been fun to watch our offense take off, and we don't undervalue any of the guys that are making that happening," Matheny said. "It just shows the depth.

"I think we all just knew as we were fighting there to score runs it was going to come. We were hoping it would come in bunches in some point, and that's what has happened. See how long we can continue it."

Michael Wacha (9-4) was the benefactor of the offensive surge. Wacha allowed three runs, six hits and two walks while striking out five in six innings.

Jason Vargas (13-6) took the loss and is 1-3 in his past six starts. He has pitched five innings or fewer in five of those starts.

Vargas yielded six runs, eight hits (two home runs) and three walks in 4 2/3 innings. He also had two wild pitches and a hit batter while striking out three.

Carpenter went 2-for-3 with an RBI double in a three-run seventh. He also was hit by a pitch and walked. He is hitting .463 with a .565 on-base percentage in 14 games at Kauffman Stadium.

Wacha, who was 5-1 with a 1.90 ERA in his previous seven starts, walked Eric Hosmer with one out in the fourth. Melky Cabrera dropped a single into center. After Mike Moustakas popped up, Jorge Bonifacio drew a walk to load the bases.

Cheslor Cuthbert, just activated from the disabled list, quickly cleared them, hitting Wacha's first offering off the base of the left field wall and just fair for a double to make it 3-1.

Vargas, however, could not hold the lead for one inning and failed to survive the fifth. The Cardinals sent 10 men to the plate in the six-run inning.

"It was one I felt like I let get away from the team right there in that fifth inning," Vargas said. "Some weird things happened, but with Cheslor coming up big in the half-inning before, there's just got to be a stop put to that inning, regardless of what happens. It's just a frustrating one to let get away."

Grichuk, the Cardinals' No. 9 hitter, led off with his 14th home run, hitting Vargas' second pitch out.

Vargas then hit Carpenter with a pitch and gave up an infield single to Tommy Pham. Jose Martinez walked on five pitches to load the bases. Molina drove in two runs with a single that hit the third base bag. Dexter Fowler's double advanced Molina to third and banished Vargas.

Mike Minor replaced Vargas and gave up a three-run homer to Gyorko on his fifth pitch, pushing the St. Louis lead to 7-3.

"It started off with a home run, pretty much a center-cut pitch, and after the hit batter, a swinging bunt, a couple of wild pitches that we couldn't block and Vargy made a good pitch on Molina that made him roll over on a three-hopper down the line that just hit the bag," Yost said. "There was the double to Fowler, and that was his night."

NOTES: Royals LF Alex Gordon was not in the lineup and will likely not start for several days. Gordon is hitting .199 with a .294 slugging percentage in 100 games. Manager Ned Yost is trying to find more offensive production, leading to the decision to bench Gordon, who appeared as a defensive replacement. ... 3B Jedd Gyorko was back in the Cardinals' lineup after sitting out the previous two games. He was dropped to seventh in the batting order. ... The Royals activated Cheslor Cuthbert off the disabled list, and he started at third base. Cuthbert missed six weeks with a sprained left wrist. Rookie INF Ramon Torres, who hit .242 in 23 games, was optioned to Triple-A Omaha. ... Mike Moustakas, who is hampered by fluid on his right knee, was the Royals' designated hitter. ... Royals RHP Trevor Cahill and Cardinals RHP Mike Leake are the probables Wednesday with the series continuing at Busch Stadium in St. Louis.