CINCINNATI (AP) - CINCINNATI (AP) - Joe Maddon looked up from his sheet of statistics and saw left-hander Cole Hamels walking toward him instead of warming up for the second inning - the last thing the Cubs manager wanted to see.
"I'm looking up off my paper and all of a sudden he's walking toward me, so I had no idea what was going on," Maddon said.
Just like that, the Cubs' rotation had taken another big hit.
Hamels walked off the field after throwing only one warm-up pitch before the second inning Friday night and feeling discomfort in his left side. The Cincinnati Reds took advantage for a 6-3 victory that ended their four-game losing streak.
The Cubs already were missing Kyle Hendricks, sidelined by a sore pitching shoulder. Hamels (6-3) exited after only one inning that included 22 pitches, a walk, two hits and a run. He's expected to go on the 10-day injured list Saturday.
Hamels will have an MRI to determine the severity of the injury, located by the left oblique.
"He's been unbelievable," said reliever Mike Montgomery, who took over for Hamels and gave up five runs. "Obviously you hope it's not serious. We're definitely going to need him."
It was a huge break for the last-place Reds, who were 1-11 career against the left-hander entering the game. Plus, Hamels had been on his best streak of the season, going at least seven innings in each of his last five starts with a 1.00 ERA.
"I'm not sure what happened," Reds manager David Bell said. "That was unfortunate for them. At that point, you're just trying to limit the damage to your bullpen."
Chicago overcame a five-run deficit for a 9-7 win on Thursday against Atlanta but couldn't pull off a second straight big comeback.
Sonny Gray (4-5) pitched shutout ball into the seventh before giving up Jason Heyward's two-run homer . Michael Lorenzen pitched out of the two-on threat in the eighth and got the last five outs for his fifth save in six chances.
The Reds play nine straight home games heading into the All-Star break, representing a chance to get into the NL Central race or remain stagnant near the bottom of the division.
"That's a big win for us," Gray said. "We need to get some momentum and finish the homestand strong."
Joey Votto had a season-high four singles and drove in a run. His third single off Mike Montgomery gave him 1,800 career hits. Phillip Ervin added a homer and a double.
Second baseman Scooter Gennett was activated after missing all season with a groin injury and had an infield single in four at-bats, failing to get the ball out of the infield. He was picked off first by Kyle Ryan after his hit.
"It felt great to get out there with the guys," Gennett said. "There was great energy in the stadium. It was awesome to see."
The Reds are hoping their struggling offense gets a boost from Gennett, who was their most productive hitter of the last two seasons. Gennett was only 4 of 26 during a minor league rehab assignment. Bell plans to play the second baseman regularly as he rounds back into form.
Votto's last four-hit game was May 18 last year. It was his 24th career four-hit game.
The Reds are 5-2 against the Cubs this season, a significant improvement. In the last four years, the Cubs were 51-25 against the Reds. The Reds have piled up at least 11 hits in six of the seven games against Chicago.
The Cubs have dropped 11 of their last 14 road games.
Cubs All-Star catcher Willson Contreras went 0 for 4, ending a 10-game hitting streak that matched his career high.
Cubs: Hendricks is scheduled to throw in the bullpen Saturday.
Reds: Left-hander Alex Wood will try to throw over the weekend. He's been sidelined since spring training by a bad back. Wood was scheduled to throw a bullpen session on Tuesday but had a setback.
Cubs: Left-hander Jose Quintana (4-7) gave up a season-high nine runs on June 22 against the Mets and got extra days between starts. He has a 6.75 ERA in his last six starts. Quintana is 0-2 in two starts against the Reds this season, giving up eight earned runs in 10 1/3 innings.
Reds: Luis Castillo (7-2) lasted only 3 2/3 innings Saturday in a 6-5 loss at Milwaukee, giving up six runs. He beat the Cubs 4-2 on May 16 at Great American Ball Park, allowing two hits in 5 1/3 innings.
More AP MLB: https://apnews.com/MLB and https://twitter.com/AP_Sports