CINCINNATI -- The Pittsburgh Pirates didn't have a home run through the first three games this season. The first one came when they needed it most.

With the bases loaded and facing a three-run deficit in the eighth inning on Friday night, Starling Marte hit his first career grand slam off J.J. Hoover helping the Pirates remain undefeated with a 6-5 victory over the Cincinnati Reds on a frigid and at times snowy evening at Great American Ball Park.

"We've been connecting well, hitting line drives and not trying to hit home runs," said Marte, via interpreter Mark Gonzalez. "I'm just glad it was me."

With the Reds leading 5-2 with the bases loaded and two outs in the eighth, manager Bryan Price summoned closer Hoover (0-1) from the bullpen.

Hoover who inherited the closer's role from Aroldis Chapman who was traded this offseason, left a 1-0 slider up in the zone and Marte sent it sailing 404 feet into the left-center field seats to put Pittsburgh ahead.

"I didn't execute that pitch to the best of my ability and he got it," Hoover said. "The weather was no excuse. I warmed up and did everything I needed to do to get ready. I just didn't execute that pitch."

It was the Pirates' first home run of the season in their 131st at-bat.

"Marte is capable of hitting a ball like that," said manager Clint Hurdle. "Historically, this hasn't been a park that he's done a lot of damage in. That's one the best swings that he's had in this ballpark."

Ryan Vogelsong (1-0) earned the victory for the Pirates who are 4-0 to start a season for the first time since 2003. For Vogelsong, it was his first victory in a Pirates uniform since Sept. 14, 2005 at St. Louis.

Both teams battled the elements, combining for five errors and four hit batters. There also were a combined 18 runners stranded.

"We kept scratching and clawing," said Hurdle. "You have to keep playing the game and create an opportunity where someone can do something."

Reds second baseman Brandon Phillips returned from missing two games due to illness and hit a solo homer, had two RBIs and scored twice.

"He was terrific," said manager Bryan Price. "It's great to have him back. He's an impact player for the ballclub."

Mark Melancon earned his second save with the help of Andrew McCutchen who made a lunging catch of Eugenio Suarez's line drive in center field.

Cincinnati (3-1) scored twice off Pirates starter Francisco Liriano in the first inning.

After Suarez singled and scored from third on a groundout, Phillips launched Liriano's first offering 401 feet into the center field batter's eye to make it 2-0.

Liriano helped his cause with an RBI double in the second for his second RBI this season. He also recorded his 1,400th career strikeout an inning later.

Cincinnati starter Alfredo Simon allowed two runs and five hits through five innings. Four of those hits came from Jordy Mercer and Liriano, who had two apiece.

The Reds had the bases loaded in the third and fourth innings but double-play grounders helped Liriano escape further trouble.

Mercer also threw Phillips out at home trying to score from second when third baseman David Freese misplayed a ground ball as the Pirates trailed 3-2 after five.

The wintry, wet conditions contributed to some sloppy play as the teams combined for four errors through five frames. Suarez committed two errors in the fifth.

"Both teams were playing in it," said Hurdle of the weather which featured a stiff wind and bands of sleet, rain and snow. "Some guys don't wear sleeves. Everybody deals with it differently."

Liriano also was done after five innings as well having allowed three runs with four walks and three strikeouts. But, Marte's heroics helped him avoid his first defeat of the season.

"He kept us in the game," said Hurdle. "He competed his backside off tonight. He's going to be fine. It was all yard work. His slider was his go-to pitch."

NOTES: Reds RHP Anthony DeSclafani will not start Sunday's series finale against the Pirates as originally planned. He is on the disabled list with a strained left oblique and still isn't 100 percent. ... The Reds named RHP Tim Melville as Sunday's starter. It will be his major league debut. … Cincinnati selected the contract of 1B Brandon Allen from Triple-A Louisville on Friday. ... Reds 2B Brandon Phillips returned to the lineup after missing two games with a stomach virus. ... The University of Cincinnati is hosting "Josh Harrison Day" on Saturday in honor of the Pirates second baseman and Bearcats alum.