"I'm a firm believer that it starts and ends on the mound," Astros manager Bo Porter said. "We sent the guy out there tonight, and when you have that kind of pitching performance, it's going to keep everyone in tune to the game and it's definitely going to give you a spark.
"What I really liked was the level of composure which he displayed. I just thought he did a great job of controlling his emotions and really honing in to exactly how he wanted to pitch these guys."
Despite the performance, Cosart admits he didn't get much sleep the night before and could barely control his nerves before the game.
"My heart was going a million miles an hour," said Cosart, who had his no-hit bid broken up in the seventh on a Ben Zobrist single. "I was just hoping I could get the ball down. My curveball and my changeup were huge for me tonight.
"The name of the game is getting balls down, changing speeds -- and I was able to do to that in the first and establish it early."
Cosart retired the first nine batters he faced, and he forced the Rays into four double plays and didn't let a runner advance past second base. He was removed for closer Jose Veras after walking pinch-hitter Kelly Johnson in the bottom of the ninth.
Luke Scott's two-out single would put the Rays on the board in the bottom of the ninth, but Veras struck out Evan Longoria to end the game with the potential game-tying run on third.
"I sent him back out there and if he goes 1-2-3, it's a complete game," Porter said. "Once that first guy got on, I wasn't going to put him in a position to get a no-decision, and we had Veras ready to close it out."
The Astros got to Rays starter David Price early, and a first-inning single by Carlos Corporan scored Jake Elmore and Chris Carter to give the Astros a 2-0 lead.
Price was efficient otherwise, giving up eight hits but throwing a complete game on just 87 pitches.
"I don't take any credit [away] from the job that Price did," Porter said. "He threw an excellent game tonight, and we knew the Rays weren't going to go away easy. They put together some great at-bats in the ninth and Veras did a good job of keeping his composure and closing the game out."
The Rays had the longest active win streak in the Majors and this was only their second loss in the last 14 games.
"The Cosart kid did a great job," Scott said. "We didn't know what to expect -- we just knew he had decent velocity. I'm sure he's pumped, he bested a very good team tonight. It was tough. He had a lot of deception. There were not too many mistakes. Good pitching shuts down any type of hitting."
Cosart said he brought about 15-20 family members and close friends to watch him in his debut. He tried not to read too much about his opponent, but he couldn't stay off the Internet.
"I try to stay away from the Internet the day before, but I looked at the Rays' website and I see 'Streaking Rays, Price pitching' and all that good stuff," Cosart said. "I wasn't aware of the no-hitter until the I saw it in the seventh, and that's probably why they got that hit.
"Still I realized how hard it is to go a complete game. I've had a couple of rainout complete games but those are just seven innings. When I came back out for the ninth inning I was exhausted. I was on adrenaline basically trying to work my way through it."