DENVER -- Rockies right-hander Cal Quantrill was certain the nagging issues that have affected his production and availability in the second half of the season were behind him by the time he returned from an 18-day absence to face the Cubs on Sunday afternoon at Coors Field.

But the problem that has led to the periodic pains of the second half showed up in a rusty performance during the 6-2 loss to Chicago.

Quantrill’s 3.30 ERA through his first 14 starts had at least those with the Rockies quietly campaigning him for inclusion in the All-Star Game. A right forearm strain led to a 12-day gap in the first half of August. The latest absence came because of right triceps inflammation, which required an anti-inflammatory shot, rest and rehab. Quantrill sees the issues this year as less worrisome than a shoulder issue that cropped up while he was with the Guardians last season, before an offseason trade to Colorado.

“It was just two or three really strenuous outings in a row, and it built up to a spot where I wasn’t where I needed to get,” Quantrill said while preparing for Sunday. “If I would’ve made a couple of those outings easier on myself, I probably would have been all right.”

"Strenuous" best described Sunday’s performance. In just 2 1/3 innings, Quantrill walked a career-high six -- topping the five walks he issued against the Marlins on Aug. 27, his most recent outing. Quantrill also gave up four hits, but allowed just two runs. The dependable grit was there, but grinding through 69 pitches while managing seven outs was excessive.

But Quantrill walked away feeling healthy.

“He told me, after the game and during the game, his arm felt great,” Rockies manager Bud Black said. “It was one of those games that, over a long season, six months, he didn’t throw strikes.”

The issues were nothing that some more time on the mound can’t fix.

Once the soreness above and below the elbow showed up, Quantrill curtailed his throwing program between starts. That’s smart for health, but it’s during catch play and bullpen sessions that Quantrill gains the muscle memory needed to self-correct during games. But in the days leading to Sunday, Quantrill normalized his throwing program.

On Sunday, however, mind and body played tricks. No adjustment worked.

“I thought I was making adjustments, but watching the video, it didn’t look like I was changing what was causing the issue,” Quantrill said. “So I’m just going to just chalk this one up to being just a little rusty. It wasn’t my best day at the field.

“When you’re going out there every fifth day, you have a good sense of what your arm is doing and what you need to do to fix something. I just need to get back on the right train and have a good week throwing.”

Quantrill wants to finish strong, but the first-half snippet and his overall work at Coors Field (a still-respectable 4.37 ERA in a difficult park) have opened eyes. But as has been the case throughout Quantrill’s career, there could be plenty of other trade suitors.

Quantrill began his career with the Padres, but was sent to Cleveland in a 2020 Trade Deadline maneuver, and the Rockies acquired him from the Guardians last November.

The Rockies believe the combination of veterans, some coming off injury, and a group of prospects they feel are close could spark a turnaround as early as next season.

However, Colorado is one of several teams trying to figure out the effects of massive changes in the television landscape, which affects revenue, which affects payroll. Quantrill, under a $6.55 million deal this year, and lefty Austin Gomber, at $3.15 million salary this season, head into their last year of arbitration, which means pay increases.

Will the Rockies deal one or both, and use associated money for other needs? Such a decision would be painful. Quantrill -- and Gomber, as well -- embraced having separate repertoires at home and on the road, and valuing winning over shiny statistics. Those traits give a man a chance in the Majors’ most challenging pitching environment.

“You can hate everything I do, but if I have a winning record then I did my job,” Quantrill said. “I ask a lot of my defenders and ask them to put up runs. But it’s not about personal metrics, it’s not about your ‘stuff-plus.’ All that is great, but we play 162 games and we need to win.”