PITTSBURGH — Elias Diaz is filling in quite nicely for injured catchers Francisco Cervelli and Chris Stewart.

Diaz drove in two runs, Ivan Nova pitched six shutout innings and the Pittsburgh Pirates beat Jeff Locke and the Miami Marlins 3-1 on Sunday.

Diaz drove in Jose Osuna and David Freese with a double in the first inning. Diaz also singled and scored on Jordy Mercer’s single in the sixth inning.

Since Cervelli went on the disabled list Wednesday with a concussion, the 26-year-old Diaz is 7 for 14 with four RBIs.

“He’s got a hit in every game he’s started, eight of them,” manager Clint Hurdle said. “He’s having a blast. Big hits. Swinging the bat aggressively. Two more hits. The big hit kind of loosens things up. And he’s done a nice job behind the plate.”

Nova also praised his defensive work.

“He’s a great catcher,” he said. “I told him right before the game, just call the game. I’m going to follow you. If I need to shake you off, I’m going to shake you off. I want you to do your job.”

Nova (6-4) allowed one hit, struck out four and walked none. He showed no ill effects from the left knee inflammation that bothered him in his previous start, but he threw only 77 pitches.

Hurdle said the decision to pull him early was offense-related and Nova said he was good to go longer if needed.

Locke (0-2) was charged with three runs and eight hits in 5 1/3 innings in his first start in Pittsburgh since he signed with Miami in free agency. The left-hander spent the first six years of his career with the Pirates.

“I thought he was OK,” Marlins manager Don Mattingly said.

Ichiro Suzuki hit his second homer for Miami in the eighth. The 43-year-old Suzuki last hit more than one homer in a season in 2013.

It was Suzuki’s 10th start of the year.

“I had to replace (Giancarlo) Stanton today, so maybe I should at least hit one,” he said.

Felipe Rivero got his second four-out save in as many days. He threw just 12 pitches.