"There are spots they're going to have to step up," Kimbrel said. "It's not a tryout, it's a 'We-have-to-go-out-there-and-do-the-job' kind of position. That late in the game, that's when games are won and lost."
Kimbrel pitched a scoreless ninth for saves in all three games of this weekend's sweep of the Dodgers. Gearrin and Avilan each picked up wins when the Braves' offense turned one-run deficits into multi-run leads in the eighth inning on Saturday and Sunday.
Avilan appears to have fully recovered from a left hamstring injury he sustained on April 16 against Kansas City. In his past six appearances, Avilan has given up just two hits and held opponents scoreless over a span of 6 2/3 innings.
"He's got one of those arms and the way the ball comes out of his hand that it's tough for hitters to pick up on, so he can just go right at guys," Kimbrel said of Avilan. "And with him having that movement and that location, it just makes him that much better."
Avilan turned in a few tentative outings immediately following his return from the injury, but the left-hander credited renewed confidence in his mechanics as the key to his recent success.
"My first couple outings after I got hurt, I felt like it might happen again," Avilan said. "So I was throwing the ball, but not really throwing the ball. I was a little bit afraid. My mechanics were different than they were at the beginning of this year and last year. In the first few outings after I got hurt, my sinker was flat from side to side. That's why a couple lefties hit easily against it. Now I feel pretty good. My mechanics feel good and my sinker is doing really good, too."
Gearrin has been similarly solid, as he has not surrendered a run in nine appearances this month.
Kimbrel, who has handled the closing duties since the start of the 2011 season, expressed confidence that his teammates would pick up where Venters and O'Flaherty left off.
"They're good pitchers," Kimbrel said. "They're not here for no reason, and I think they know what they're doing out there. It's just the situation's going to change a little bit, and I think we'll be fine."
Mark Bowman is a reporter for MLB.com. Eric Single is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.