Jackson hit his first career home run to help Raley earned his first major league win, leading the Cubs to a 9-7 victory over the Cincinnati Reds and a split of their day-night doubleheader on Saturday.

Starlin Castro had three hits and two RBIs as the Cubs rebounded after losing the first two in the four-game weekend series. David DeJesus added his fifth home run of the season in the ninth.

The Cubs are working on a new contract for Castro, but general manager Theo Epstein said nothing has been finalized yet. It's easy to see why the Cubs are interested in locking up the talented shortstop.

"Castro is just one of those players," manager Dale Sveum said. "He came up huge again. We found a slot for him at cleanup. It is what he does. He cuts and slashes."

Ryan Ludwick went deep twice and drove in three runs in the nightcap for the Reds, who had won seven of eight. Ludwick's fourth multihomer game of the season left him tied with Jay Bruce for the team lead with 25 homers on the year.

"It's tough to sweep a doubleheader," Ludwick said. "We had opportunities. They came out and scored a big run at the end. Our backs were against the wall, but we scratched and clawed and fought and gave ourselves a chance."

Raley (1-2) gave up four runs, three earned, and five hits in 5 1-3 innings. He also singled for his first major league hit.

"I'm really fired up right now," Raley said. "You have to execute your pitches here. Ludwick got me. I got the ball from my first hit and that's awesome too. I told the coaches I could hit a little bit. They didn't believe me."

The Reds won the opener 5-3 behind ace Johnny Cueto, who pitched eight crisp innings. Todd Frazier also had a go-ahead homer for the second straight game.

The Cubs jumped all over Todd Redmond in the nightcap. Redmond (0-1) gave up four runs and seven hits in 3 1-3 innings in his major league debut. He struck out two and walked five.

Redmond was the sixth pitcher to start for Cincinnati this season. The Reds used the same five starters for the first 120 games, a modern franchise record and a key reason for their surge to the top of the NL Central.

Jackson sparked the Cubs' 13-hit attack with a drive into visitors' bullpen down the right-field line on a 1-1 pitch in the second, making it 1-0.

"It is something I can cross off my list," Jackson said. "I keep crossing things off my list."

Jackson is expected to be big part of the Cubs' future. Even though he struck out three times after the home run, Sveum sees positive signs.

"Things are getting a little bit better," Sveum said. "He struck out three times but the slugging percentage is there along with his defense and speed. He is having better at-bats."

Chicago built an 8-2 lead, then held on as the Reds battered its beleaguered bullpen. Carlos Marmol worked the ninth for his 15th save in 17 chances.

"Marmol has been very good for quite a while," Sveum said of his closer, who lost his job temporarily when the Cubs were in Cincinnati in April.

The NL Central-leading Reds came out of the doubleheader with a 6½-game lead over second-place Pittsburgh.

Cueto (16-6) gave up two runs and three hits, drawing a standing ovation when he walked off the mound for the last time. He also hit DeJesus, the first batter of the game.

Cueto, who didn't allow a runner past first base after the first inning and retired 19 of the last 20 batters he faced, is the first Cincinnati pitcher since Danny Jackson in 1988 to win 16 of his first 25 starts. He has won seven of his last eight appearances to move into a tie with Tampa Bay's David Price for the major league lead in wins.

Aroldis Chapman allowed two hits, a walk and a run -- his first in 24 appearances -- but held on for his 29th save.

Cubs slugger Alfonso Soriano drove a 3-2 pitch 433 feet into the second deck in left field with two outs in the first inning for his 22nd homer. The two RBIs gave Soriano 1,000 for his career.

Jeff Samardzija (8-11) gave up four runs and six hits in five innings for Chicago. He struck out five, walked none, hit a batter and threw a wild pitch.

The right-hander is 1-3 with a 4.07 ERA in four starts this month.

Game notes

Both teams recalled pitchers from their Triple-A affiliates to start the second game of the doubleheader. The Cubs promoted Raley from Iowa, while the Reds recalled Redmond from Louisville. ... Neither team was required to send anybody out to make room. Major League Baseball rules allow teams to add a 26th player to their active roster for doubleheaders such as Saturday's, which was scheduled after a May 1 postponement. ... Soriano joined Barry Bonds, Andre Dawson, Willie Mays, Alex Rodriguez and Gary Sheffield as the only major league players with at least 1,000 RBIs, 400 doubles, 350 home runs and 250 stolen bases in their careers.