DENVER -- Rockies shortstop Troy Tulowitzki was unburdened of scar tissue that impacted a nerve in his left groin area, thanks to a surgery last week. Monday, he put down the weight of a secret he kept earlier in the year.

The pain he was experiencing was at the root of a strange slump in which Tulowitzki made six errors in the season's first 11 games, after making six errors for all of 2011, when he earned his second straight Gold Glove Award.

Most of the errors were on throws, which was alarming because his laser arm separated him from most others at his position. Unable to torque his body into positions that allowed him to make such throws without pressuring his arm limited his ability. Tulowitzki admitted at the time that he was thinking about throwing, and not just reacting. On Monday, he revealed why.

"Since I have been here I take defense seriously and want to be the best defender out there," Tulowitzki said. "It was tough to take, but there are all kinds of things that guys deal with in this game, not just me.

"I wasn't able to throw on the run. Like I said, I never thought about throwing. I was thinking about planting my feet and throwing, because I didn't want certain areas to hurt."

Tulowitzki found a way to stop the pain from affecting him and has just eight total errors in 47 appearances. He also batted .287 with eight home runs and 27 RBIs.

Tulowitzki said the root of the scar tissue was a torn quadriceps tendon he suffered in 2008. He underwent surgery and missed 47 games. He has dealt with various leg muscle issues since. Dr. Bill Meyers, a noted Philadelphia surgeon who is an expert in sports hernia and similar injuries, conducted the procedure.

"Initially, I had that quad injury in San Francisco [in 2008], so I had to work a little extra in that area," Tulowitzki said. "So it was just the wear and tear."

Tulowitzki said he is being limited to walking a mile a day. With triple-digit temperatures, Tulowitzki is doing his walking inside Coors Field's hallways.

He's trying not to let his team's struggles get him upset.

"It's tough to take, watching games," he said. "You never want to sit there and watch your team. You want to be out there trying to help them win ballgames. It's been a tough year, but there's still time to maybe turn this around and hopefully maybe get some of these young kids better. You never know what's going to happen."

Chacin getting closer to return

DENVER -- Rockies right-handed pitcher Jhoulys Chacin is inching closer to full health and itching to interject some hope into his team's season.

Chacin, who hasn't pitched since May 1 because of a nerve issue on the right side of his chest, is scheduled for a light bullpen session on Tuesday.

Last Friday, he threw 15 pitches off the mound with a catcher positioned in front of home plate and 15 more pitches to the catcher positioned right on home plate. This next session, the catcher will be right at the plate for 15 and in a normal position for the next 15.

Chacin was expected to emerge as a star, but his season was miserable -- 0-3 with a 7.30 ERA in five starts -- before he went to the disabled list. The Rockies planned to option him to Triple-A Colorado Springs before Chacin admitted what many had suspected -- that he was hurt. The problem was undefined until he visited a vascular specialist in St. Louis.

With the current rotation foundering, Chacin sits and watches, along with right-hander Juan Nicasio, coming back from a strained left knee, and left-handed veteran Jorge De La Rosa, who has had multiple setbacks in his return from last year's Tommy John elbow surgery.

Nicasio is slated to face live hitters on Tuesday.

Chacin realizes that if he returns and pitches well, it could settle some fears about the future of the rotation.

"It is frustrating for Nicasio, De La Rosa and me -- pitchers who have been here," Chacin said. "We see the games. I believe if we get healthy, we can help the team win some games and show the fans and everybody that we can pitch.

"We're not having the best time right now, but we can pitch and help our really good offensive team. We can get better. You never know what can happen."

Worth noting

• Monday's gametime temperature of 100 degrees was the highest in 20 seasons of Rockies home games. Five other games started at 97 -- one at Mile High Stadium and the others at Coors. The last game that started at 97 degrees was against the Pirates on June 7, 2006.

The daytime high at Denver International Airport was 105, which tied a record.

The heat comes at a difficult time, as multiple wildfires are burning throughout Colorado.

• Veteran catcher Ramon Hernandez, who has missed 29 games with a strained left hand, played catch at Coors Field on Monday.