Hernandez's two-run homer in the ninth inning barely cleared the fence in right field, sending the Reds to a 2-1 victory over the Houston Astros on Friday night.
"I was lucky it got out," Hernandez said. "I was just trying to get a single and maybe get a run to tie the game. When I hit it, I didn't think it was out. It just took off."
"Everything is fine, I am OK," Valverde said. "The guy just hit a home run. What else am I going to do? It was a fastball and I threw my best pitch to this guy, and he hit it.
"Tomorrow is a new day. I had a little bit of a back, but not too much, just a little bit."
Roy Oswalt allowed five hits and walked three in six shutout innings for Houston. The right-hander is 23-1 with a 2.39 ERA in 29 games, 27 starts, against Cincinnati in his career.
Johnny Cueto walked six in 4 2/3 innings for the Reds. He gave up one run and two hits.
Oswalt looked shaky early, working out of a bases-loaded jam in the second with a pair of strikeouts and stranding runners at first and second in the third by getting Jay Bruce to pop up for the final out.
Cueto walked three in the fifth inning, including Lance Berkman with the bases loaded to give Houston a 1-0 lead.
"This would have been a real tough loss," Reds manager Dusty Baker said. "They didn't really deserve to win it but they were winning in the ninth. We walked in that run to get behind.
"But they walked a guy in the ninth and that got them in trouble too."
The Astros announced they will recall RHP Felipe Paulino from Triple-A Round Rock to start Sunday's game. Paulino is 1-0 with a 1.75 ERA in two starts for the Express this season. A corresponding roster move will be made before the game. ... Astros 2B Kaz Matsui sat out his third straight game with a sore back. ... Hernandez had his 4,000th career at-bat in the seventh inning.