Strong starting pitching helped the Pittsburgh Pirates gain a share of first place in the NL Central.
It's also been the biggest reason behind their success at home against the Chicago Cubs.
Charlie Morton, though, is looking to beat the Cubs for the first time in over three years Friday night at PNC Park.
Pittsburgh (85-61) is getting a 2.39 ERA from the rotation during a four-game winning streak, and Jeff Locke turned in the latest impressive effort in Thursday's 3-1 win over Chicago.
Locke yielded one run and three hits in seven innings in the opener of this four-game set, becoming the third Pirates' starter over the last four games to give up one run or none.
"It was intent, conviction and execution," manager Clint Hurdle said. "All three of them were covered off the mound by Jeff."
Facing the Cubs (62-84) should give the Pirates a chance to at least keep pace with St. Louis atop the division. The Cardinals are opening a three-game set with Seattle.
Pittsburgh's rotation has dominated the Cubs at home this year, compiling a 1.88 ERA to overcome the offense's 2.7 runs per game and .187 average to win five of seven meetings.
Morton (7-4, 3.44 ERA), though, is 2-4 with a 5.80 ERA in seven career starts against the division rival, losing the last two while surrendering eight runs with eight walks in 10 1-3 innings. He hasn't defeated Chicago since May 5, 2010.
The right-hander also started the Pirates' most recent defeat, 9-2 at St. Louis on Sunday. It was his shortest outing of the season, as discomfort in his left foot forced him to exit with two outs in the second inning after allowing five runs. He was 4-0 with a 1.74 ERA over his previous six outings.
"He was getting some pitches up, and also fell behind," catcher John Buck told the team's official website. "Still, it wasn't like they were hitting him that hard."
Andrew McCutchen, who had a double and scored a run Thursday, is certainly hitting the ball hard. The star center fielder has at least one hit in all 10 games this month, batting .457 with two homers, three doubles, one triple, five RBIs and eight runs.
McCutchen is hitting .424 (14 for 33) with five doubles, four RBIs and six runs over his last nine meetings with the Cubs, and he's 2 for 6 off scheduled starter Jake Arrieta.
Chicago has split its last 12 games, and has been feast or famine at the plate. The team is batting .311 with 12 homers and 39 runs in those victories compared to .170 with four home runs and 10 runs in defeat.
The Cubs mustered four hits in the opener.
Anthony Rizzo had one of those hits, but is 1 for 18 with five strikeouts over the past five games. The first baseman is also batting .209 on the road, and is 2 for 26 with a homer and three RBIs at Pittsburgh this year.
Arrieta (2-2, 4.28) has won both of his career starts against the Pirates with a 3.00 ERA and 11 strikeouts in 12 innings.
The right-hander is trying to rebound from Saturday's 5-3 loss to Milwaukee, giving up four runs with three walks while hitting a batter in five innings.