He entered the season's final month with a 3.88 ERA, which would have been his highest in the last four seasons. The September slump inflated his final figure to 4.32 in 72 appearances, covering 73 innings. He finished 2010 at 2.93 in 76 games, 3.25 in 74 games in 2011 and a 3.71 in a National League-leading 80 games in 2012. It adds up to 302 appearances over four seasons.
Belisle never complained of fatigue or pain. He blamed the struggles on being too predictable, especially against National League West foes. Five of the six rough games were within the division. His final appearance included a scoreless inning in Saturday night's 1-0 victory over the Dodgers, the division champs. Two of his final five scoreless games were against the NL West.
"The losses still make nights tough," Belisle said. "But some of the roadblocks that I've hit this year, I'm very proud of how I persevered and came out on the right side of them. I think this one is new. I've had to adapt. I want to continue to understand what that was, have the foot on the throttle to make sure I'm continuing to adapt and improve.
"There's no complacency. There's just that uncomfortable feeling of continuing to perform. I like that. I like the challenge. There's an opportunity. I didn't want the season to end."
Manager Walt Weiss used Belisle a little less in September, but his vocal support hasn't wavered.
"You guys know what I feel about Matty," Weiss said. "I like when he's out there, because he's as mentally tough as anybody. I like when he's in a game, a tight game, with the game on the line. I like having him out there."
Still, Belisle's future falls more into the category of a tough decision than a no-brainer. The Rockies have several of those within their. bullpen.
In addition to Belisle's option, the Rockies must make arbitration decisions on right-hander Wilton Lopez, who appeared in more games (75) and threw more innings (75 1/3) than Belisle and also had lengthy periods of struggle; lefty Josh Outman, who finished the year receiving late-game and specialist opportunities with mixed results; righty Mitchell Boggs, whom the Rockies acquired in a trade after he struggled mightily when given the Cardinals' closer job early this season; and righty Manuel Corpas, who bounced between the Rockies and Triple-A Colorado Springs and pitched well more often than not when called upon in close games in September.
The Rockies are not expected to pick up a $4.25 million option on closer Rafael Betancourt, who recently underwent Tommy John surgery on his right elbow and is expected to miss 2014. In recent years, Belisle and Betancourt have been advisers and leaders to younger relievers.
The building of the bullpen will be a closely watched project.
Lefty Rex Brothers pitched well enough to be the first choice for closer next season, but the Rockies need a plan for holding leads for him to close. Righty Adam Ottavino responded well to being given late-inning chances. Other jobs are up for grabs, and the Rockies figure to look at trades and free agency to improve.
Colorado needs durable relievers, but also must be ready in case they become worn.
Belisle has made 302 appearances over the last four seasons, more than any reliever in the Majors, and his 317 innings pitched are second-most to the 323 of the Nationals' Tyler Clippard. Lopez, who joined the Rockies this season in a trade with the Astros, has the seventh-most appearances at 280 and the sixth-most innings at 279 2/3. This year, the Rockies had Lopez, Belisle and Brothers among the top 20 in the NL in appearances. Ottavino's 78 1/3 innings were fifth-most in the NL. So, the team has to have quality depth and some foresight into wear on its relievers.
If Belisle is extended, the Rockies will have to determine if he fits in the eighth inning, where he has made 103 appearances the last two seasons, or earlier. Beslile has some control over his return. His decision is based on the Rockies backing the in-house feeling that they're not far from contending, and could do so quickly.
"As long as we have a competitive chance to win and I'm treated fairly, which I have been my entire tenure here, I love this place," Belisle said. "Nothing's changed from my end. I've got a lot left in me. I love this place. I still want to hold the trophy here. I just want to contribute in a significant way to a winning club.
"I like the ball in big situations, but the trick is what part of the puzzle are you to a winning organization? I've always said that."