Updated

(SportsNetwork.com) - Good teams have great players. Great teams have others who can pick up the slack when the normal go-to guys aren't performing up to par.

Such is the case with the Pittsburgh Pirates as they head to Chase Field on Thursday night to open up a four-game series with the Arizona Diamondbacks.

The Pirates enter the series in the thick of the chase for both the National League's Central Division title as well as the league's two wild card playoff berths.

Unheralded left-side infielders Josh Harrison and Jordy Mercer have helped carry the load recently while reigning NL MLVP Andrew McCutchen has stumbled. Harison has homered in four straight games and Mercer is 6-for-15 in the same stretch while scoring three rims and homering once himself.

No Pirates player has homered in five consecutive games in eight years.

Meanwhile, McCutchen hasn't gone deep in 13 games and is 1-for-18 in his last five games.

"We call it game-time pop," manager Clint Hurdle said.

Mercer went deep in his only career at-bat against Arizona's scheduled starter, Josh Collmenter, who was gashed for six runs and 11 hits while recording just eight outs in his last start on Saturday against Philadelphia.

Chase Field has been good to him this season, though, providing five wins in seven decisions ver 10 starts with a stingy 2.89 earned run average. In his last four games there, in fact, he's 3-0 and has allowed just three runs in 20 innings.

In four lifetime starts against the Pirates, his ERA is 1.59.

On the other side, Pittsburgh starter Jeff Locke went eight starts with a 2.38 ERA before he wasnicked for six runs on 10 hits in an 8-1 loss at Colorado on Saturday.

He's allowed more than six runs just once in his career -- against the Diamondbacks -- in August 2013, when he gave up eight runs on 10 hits in just 2 2/3 innings of a 15-5 loss. In one meeting this year, though, he gave up two runs in eight innings of Pittsburgh's 3-2 win on July 1.

On Wednesday in San Francisco, Gregor Blanco had three hits and two RBI and the Giants beat the Pirates, 7-5, in the finale of a three-game series to snap a six-game losing streak.

Harrison and Mercer each hit a two-run homer off Giants starter Tim Lincecum for the Pirates.

In Cincinnati, Paul Goldschmidt and Didi Gregorius hit two-run homers, boosting the Diamondbacks to a 5-4 win over the Reds.

Goldschmidt, who was mired in a 1-for-18 slump heading into his third at-bat of the game, hit his 19th of the season to break a scoreless deadlock in the sixth. Gregorius added a crucial shot in the top of the ninth inning to make it 5-1 before the Reds rallied in the home half to make things interesting.

Wade Miley (7-7) pitched 6 2/3 scoreless innings for Arizona, which won a series at Great American Ball Park for the first time since 2011.

The win also gave manager Kirk Gibson his 337th victory with the club, matching Bob Melvin's franchise record.

Pittsburgh took two of three from the D-backs earlier in the year.