SAN DIEGO — A late addition to the starting lineup, Adam Rosales made the most of the opportunity.

Rosales, inserted into the lineup after Matt Kemp was traded to Atlanta, homered leading off the 10th inning to give the San Diego Padres a 2-1 victory over the Cincinnati Reds on Saturday night.

"That was definitely a huge win for us," Rosales said. "The pitching was awesome. It was fun baseball today."

Rosales sent a 2-2 pitch from Jumbo Diaz (0-1) over the fence in left-centre field for his eighth homer of the season, and his first game-ending homer in the major leagues.

"It was 2-2, and I threw the fastball but the ball ran into the middle and he got me on that pitch right there," Diaz said. "I feel really good. I'm comfortable and making my pitches. Tomorrow is another day."

Kemp was in the original lineup in right field before he was scratched shortly before the game. Rosales slotted in at third base, and a number of batters shifted up in the lineup to fill Kemp's void. Kemp was in the dugout during the game, but was spotted hugging teammates and exiting to the clubhouse as the trade was finalized.

The Padres later announced Kemp had been traded to the Braves in exchange for Hector Olivera.

"He was a huge part of our team," Rosales said. "It is a game of adjustments. We have a lot of great ballplayers on this team, and we can pick up and fill in that spot the best we can."

San Diego relievers Jose Dominguez, Ryan Buchter, Brandon Maurer and Brad Hand (3-2) each threw a scoreless inning.

"It was big," Padres manager Andy Green said. "I thought all four of those guys, from Dominguez all the way through Hand, were outstanding.

Christian Friedrich started for the Padres and pitched six innings while giving up one run and five hits. Friedrich struck out two and walked one.

"I definitely felt better this outing. It was coming out nice. The defence was making plays behind me, everyone was. It was a good team win all around."

Anthony DeSclafani allowed one run on four hits in six innings for the Reds. He walked two and struck out six.

"It was a well-pitched and well-defended game," Reds manager Bryan Price said. "It ended up being a situation where one run was going to decide that ballgame, and it happened to be Adam Rosales who wasn't even in the lineup before the Kemp trade."

The Reds got on the scoreboard first on Billy Hamilton's RBI single in the top of the third.

Joey Votto singled in the fourth to extend his hitting streak to 14 games.

Alexi Amarista, who had three hits in the game, hit an RBI single to right in the sixth to tie it.

TRAINER'S ROOM

Padres: Alex Dickerson was held out of the lineup one day after suffering a hip contusion. Dickerson is not expected to land on the disabled list, according to manager Andy Green. "We'll get him back here soon," Green said..Single-A pitcher Chris Paddack, who the Padres recently acquired from Florida, will have Tommy John surgery, the club announced.

UP NEXT

Reds: Homer Bailey (0-0) will make his season debut after returning from having Tommy John surgery in May 2015.

Padres: Paul Clemens (1-1, 4.82) will make his second start for the Padres after being claimed off waivers on July 1.