DENVER -- The San Diego Padres have won seven of 10 games from the Colorado Rockies this season. The latest victory was a stunner -- a 7-5 win that came when the Padres scored four runs on four straight two-out hits in the ninth, the last a three-run homer by Wil Myers.

The Padres have won the first two games of each of their previous three series with the Rockies this year and will try to continue that success behind Erik Johnson, who will make his Padres debut. They acquired him June 4 in a trade with the White Sox that sent James Shields to Chicago.

"We'll have a game plan for him," Padres manager Andy Green said before Friday's game. "We've seen these guys a lot so it's not like we can't feed him some good information how to attack these guys. The neat thing is he's actually pitched here in interleague. He's got some familiarity with this ballpark."

Johnson made a start at Coors Field with the White Sox on April 9, 2014, and threw 107 pitches in 5 2/3 innings while allowing nine hits and four runs in a no-decision as the White Sox lost 10-4.

Johnson is 7-6 with a 4.50 ERA in 18 career starts spread over four seasons with the White Sox, including two this year when he went 0-2 with a 6.94 ERA. At Triple-A Charlotte this season, Johnson went 2-1 with a 2.94 ERA in eight starts. He allowed 44 hits and 17 walks in 49 innings with 35 strikeouts.

"I've had a couple Septembers (in the majors)," Johnson, 26 said. "I've had a lot of spot starts, helping out the rotation when needed. I've been kind of waiting for my time, for my card to be pulled. I think the Padres are giving me an opportunity to go out and pitch."

The Rockies will counter with Tyler Chatwood, who allowed one run and one hit in eight innings Monday at Dodger Stadium with four walks and five strikeouts. In that 6-1 win, Chatwood became the second Rockies pitcher to pitch eight or more innings and allow one or fewer hits. The other is Ubaldo Jimenez, who threw the only no-hitter in Rockies history on April 17, 2010, at Atlanta.

Chatwood is 7-4 with a 2.79 ERA overall. At Coors Field, he's 2-4 with a 5.30 ERA in six starts. On the road, he's 5-0 with a 0.65 ERA in six starts. Against the Padres, Chatwood is 2-0 with a 3.42 ERA in six games.

Chatwood has given the Rockies a big lift this season after missing most of the past two seasons due to Tommy John surgery. In a more subtle way, second baseman DJ LeMahieu has also given the Rockies a boost.

He hit .301 last year with six homers and 61 RBIs, all career-high figures, and a career-high-tying 21 doubles. This season, LeMahieu is hitting .305 in 56 games and exhibiting more power with 15 doubles, four homers and 21 RBI. His slugging percentage is .458; last year it was .388.

"He's just maturing as a hitter," manager Walt Weiss said before Friday's game. "He's just discovering more power as he matures. He's always had the great ability to barrel up the ball, the great hand-eye (coordination). He's using his lower half more, just growing as a hitter. You watch his (batting practice) and it's more impactful. (He's) just getting in a better, more powerful position throughout the swing."