DENVER -- The music in the clubhouse was muted.
The conversation among the players was hushed.
So much for the victory celebration.
Yes, the Giants beat the Rockies, 5-1, on Wednesday night at Coors Field.
No, there weren't any giggles or grins.
Yes, the Giants bounced back well from that walk-off loss the night before, when Tyler Colvin's go-ahead double in the top of the ninth was overshadowed by Rockies third baseman Nolan Arenado's two-run double in the bottom of the inning that gave the Rockies a 5-4 victory.
No, there were no high-fives.
What's to celebrate?
Starting pitcher Matt Cain pitched three no-hit innings, and never came out for a fourth, the victim of a right hamstring strain he felt on the last pitch of the third, a called strike three on Charlie Blackmon.
And then, with two out in the top of the ninth and that four-run lead, bullpen stalwart Santiago Casilla, in only the fifth plate appearance of his big league career, hit a ground ball to shortstop, and his bid for an infield single ended when he fell over the first-base bag, and rolled on the ground in pain from a right hamstring injury of his own.
Manager Bruce Bochy wasn't looking for any heroics. He just let Casilla hit because he was hoping to get a second inning of work out of him, and not have to bring in another reliever.
"I was shocked he ran like that," said Bochy. "I told him, `Don't even swing the bat.' I've never seen him run that fast."
Talk about the agony of victory.
The Giants are sitting atop the NL West, three games in front of the second-place Rockies, and four up on the third-place Dodgers. There are, however, 115 games left. And for a portion of those games, at least, they know they will be missing a key cog in a rotation that helped them win two World Series in the last four years, Cain, and a reliever the Giants consider the unsung hero of the bullpen, Casilla.
"The win was great," said Hunter Pence, whose leadoff home run in the fourth got the offense started. "But that's a huge blow, losing Cain and Casilla."
The severity of the injuries won't be known until after both undergo MRI exams on Thursday. Cain, however, seemed at least hopeful, saying he felt the tweak on that final pitch, and didn't feel he did any serious damage.
The picture wasn't as clear with Casilla, who had to be helped off the field, and walked gingerly in the clubhouse, struggling to get the flexibility in his right leg to put on his jeans, socks and shoes.
And hanging over it all is the memory of that earlier visit to Coors Field this season when reliever David Huff strained his left quad beating out an infield single in the third inning of an 8-2 loss on April 21, and was sidelined until May 13.
"That's weird," said Jeremy Affeldt. "Two trips here and we've lost three pitchers."
Oh, the Giants can fill the spots. They can move Yusmeiro Petit, the long reliever, into the rotation until Cain is ready to return. He was in the rotation at the end of last year, and has made three starts this year, including last week when the Giants had to skip Tim Hudson for a turn.
And they can look to call up two relievers to take the place of Petit and Casilla in the bullpen. And the Giants do feel good about the abilities of several pitchers with Triple-A Fresno. Jake Dunning and George Kontos made big league cameos this year. Heath Hembree made an impression last September with 7 2/3 scoreless innings in nine appearances.
"I did a rehab at Fresno and there are four, five guys down there who can pitch at the big league level," said Affeldt. "I think Bochy, [general manager Brian] Sabean, and Rags [pitching coach Dave Righetti] agreed in the winter that they needed some protection down there.
"Our bullpen is not a group of spring chickens, so we had to have guys who can step in."
It's not, however, the same, regardless of who gets the call.
Cain is a stalwart in the rotation.
And Casilla is, according to Pence, "very underrated. He is huge for us, as many tight games as we play. To see him go down like that is tough."
Casilla has, after all, appeared in 22 games this season, working 26 1/3 innings and compiling a 1.37 earned run average.
"He's the comfortable go-to guy for Bochy," said Affeldt. "When [Bochy] needs a big out he knows he can go to him, and he gets the job done, like [Wednesday]. He comes into tight situations, and gets a double play or tough punchout."
Casilla got the call on Wednesday with the Giants leading by 5-1, after the Rockies loaded the bases with nobody out in the bottom of the eighth, and proceeded to get Michael Cuddyer to ground into a double play, and Troy Tulowitzki to fly to left field.
Moments later, however, with two out in the top of the ninth, Casilla made his ill-fated dash for first.
And the victory celebration in the visiting clubhouse at Coors Field was muted.
Tracy Ringolsby is a columnist for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.