Royals-Rockies Preview

If the Kansas City Royals are to continue their surge, they likely must find a way to end Jorge De La Rosa's current success at Coors Field.

Looking for a fourth consecutive victory, the AL Central-leading Royals try to prevent the Colorado Rockies' left-hander from winning his sixth straight home start Wednesday night.

Omar Infante had four hits with four RBIs and James Shields threw six solid innings as Kansas City (70-55) won for the 22nd time in 27 games, 7-4 at Colorado on Tuesday. Owners of a two-game lead over second-place Detroit, the Royals have won 11 of 13 on the road during stretch and extended their interleague winning streak to seven games.

Infante, who had three doubles, was 4 for 37 with no doubles and two RBIs in his previous nine games. However, he's hitting .432 with 10 RBIs in his last nine against Colorado (49-76).

''Omar's swing is so simple, it's not a lot of moving parts,'' said manager Ned Yost, whose team is 15-4 versus the NL. ''He can get on a streak in a hurry.''

The Royals own a 31-15 scoring advantage during a four-game winning streak against the Rockies, but could be in for a stiff challenge versus De La Rosa (12-8, 4.32 ERA).

While the left-hander is 4-6 with a 5.35 ERA in 13 road starts, he's 8-2 with a 3.30 ERA in 12 at home. He's posted a 2.97 ERA during a home winning streak that reached five straight starts Thursday after giving up three runs in seven innings of a 7-3 victory over Cincinnati.

De La Rosa, who has lasted at least six innings in 10 straight starts overall, tweaked his Achilles while batting in that contest but expects to pitch.

''It was bothering me a little bit,'' he said. ''But I was able to keep pitching in pain."

De La Rosa, who was with the Royals for part of 2006 and all of 2007 before being dealt to Colorado, faced them one other time and allowed two earned runs in 4 2-3 innings of a 7-3 loss at Kansas City in 2008.

Infante is 4 for 10 against him.

Kansas City's Danny Duffy (8-10, 2.60) opened August by winning three straight starts but has a 3.71 ERA over that span. The Royals have scored 23 runs in those contests, including five while he gave up two earned runs in 5 1-3 innings of a 6-5 victory at Minnesota on Friday.

In the left-hander's only previous start against the Rockies in 2011, he was roughed up for five runs and nine hits in five innings of a 9-0 loss at Coors Field.

Justin Morneau has faced Duffy the most of any Rockie, but is 1 for 8 with two strikeouts. Morneau batted .432 during a 10-game hitting streak that ended with his 0-for-4 night Tuesday.

Colorado's Drew Stubbs and Nolan Arenado each had three hits with a homer and combined for three RBIs.

Stubbs is 7 for 11 with two doubles, two home runs and six RBIs in the last three games. Arenado is 6 for 11 against the Royals this season.