Colorado's eight shutouts tie the team record set in 2001 and '02. The team doubled the number of shutouts at home this year with six.
Rockies pitchers have thrown three two-hitters, and for the second time in team history, threw back-to-back complete games.
The team is on pace to set several single season records including lowest team ERA, lowest home ERA and fewest hits and walks per nine innings.
If the record book could talk, it would have something to say to former Rockies infielder Jeff Cirillo, who on Tuesday said most of the Rockies' pitching success is because the team stores game balls in a humidor.
Rockies manager Clint Hurdle can talk, and said giving his starters freedom to play has helped them show their best stuff.
"I'm just so pleased with the development of them," Hurdle said. "Our guys took the challenge early and have run with it, and they take a lot of pride going out there."
Cirillo says: Cirillo, now a backup infielder for the Brewers, enjoyed his two years hitting in the old Coors Field. Now visiting Coors Light Field, he had plenty to say, accusing the Rockies of switching between humidor and non-humidor balls based on the game situation and flat-out saying the team is "cheating."
"Say they get behind by a bunch of runs in a game. Who's to say that can't break out the non-humidor balls?"
Would the Rockies really do that?
"Yeah," said Cirillo, who argued that MLB officials are not watching the balls as the move from the humidor to the umpire. They are [cheating]. The balls are not the same. I'm not the first one to complain about it."
Hurdle got a laugh when he was told what Cirillo said during a weekly radio interview in Milwaukee. Cirillo played for Colorado in 2000 and '01 -- a year before the humidor was first used.
"I guess everyone's entitled to their own opinion," said Hurdle, who has been questioned all season about his strong starting staff and the affect the humidor has. "I think that's what the Bill of Rights [said] isn't it? Or something we wrote up a long time ago.
"You're not allowed to cheat. The balls that we send in are tested and the humidor is regulated."
Several other visitors to Coors Field have also grumbled about the balls used.
Oakland's Mark Kotsay complained prior to a game in Denver in June. He asked A's manager Ken Macha, "They're storing balls in a humidifier? Can they do that? You can feel that they're different. No doubt -- they're a little larger, a little harder, a little weighted. Maybe they're staying in [the humidor] too long."
Still others credit the Rockies' pitching staff for the improvement.
"The humidor has been here for three or four years," Texas manager Buck Showalter said during a visit earlier this season. "People are always looking for reasons not to give people credit. That's not fair to their pitching staff."
Cirillo's not so sure the Rockies pitchers are that good.
"I know everyone says that they have better pitchers," Cirillo said. "But I have a hard time believing that Mike Hampton [a Rockies bust in 2001 and 2002] isn't a better pitcher than what they've got now. That's not to say the guys they have now won't be good -- that [Aaron] Cook guy is good. [Jeff] Francis is good -- but for them to have eight shutouts at this park, most in the National League ... you can't just say it's the pitching."
To Hurdle, it's just Cirillo being himself.
"Jeff's always been a creative thinker," Hurdle said. "He's always been able to think outside the box."
Injury update: Injured reliever Chin-Hui Tsao, who is rehabbing after having surgery to repair a torn rotator cuff, faced batters for the first time since he last played May 11, 2005.
He threw a simulated inning (15 game pitches plus warming up), and the initial reviews were good.
"He threw a little harder than I expected," said head athletic trainer Keith Dugger, who watched alongside Hurdle, general manager Dan O'Dowd and several other coaches.
Dugger said the adrenaline of finally seeing hitters helped push up Tsao's velocity. Before suffering the injury, he had reached 100 mph several times.
O'Dowd said it's too early to tell anything.
"He was free and easy" was all O'Dowd said he could say.
If Tsao is feeling good and suffers no setbacks recovering, the next step is pitching another batting practice or bullpen session, Dugger said.
Ryan Speier, out for the season with a torn labrum in his right shoulder, threw off the mound for the first time on Tuesday -- 20 throws to a standing catcher and five to a crouched catcher. He will next throw a full bullpen session and hopes to return to pitch in the Arizona Fall League.
A two-day break: Hurdle said Garrett Atkins, barring any unfortunate incident, will sit in Wednesday's series finale, giving him two straight off days with the off-day Thursday. Jamey Carroll sat Tuesday night, with Jason Smith starting at second. Hurdle said before the series he would try to rest many of his regular starters.
Up next: The Rockies will close out their three-game set with the Brewers on Wednesday night at 7:05 p.m. MT. Byung-Hyun Kim (6-6) will face Tomo Ohka (3-1).
Matthew Borenstein is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.