Astros cognizant of young starters' workloads

BOSTON -- As the season progresses, the Astros are going to be keeping close tabs on the workload of their starting pitchers, especially rookie right-handers Lance McCullers Jr. and Vincent Velasquez. They're both on pace to shatter their career-high marks for innings pitched.

The Astros are poised to be in the playoff race into September, so they won't be in a position to shut either one down and will have to get creative. General manager Jeff Luhnow said one option could be going to a six-man rotation once rosters are expanded in September.

"It allows the guys to get a little extra rest," Luhnow said. "We need to think about what the impact is. There might be some guys who don't want to do it, and we'll figure that out. We've got to be creative in giving our young players rest because if we go to the playoffs, they'll all reach their career highs and go well beyond them. We want to win this year, but we also want to be cognizant of not doing anything to injure those guys."

McCullers entered his start Sunday with a combined 82 1/3 innings pitched between Double-A and the Major Leagues. His career high for innings is 104 2/3 in 2013. Velasquez, who began the year on the disabled list, has thrown a combined 52 innings. His career high is 124 2/3, also in '13.

The Astros could slot McCullers and Velasquez at the end of the rotation coming out of the All-Star break to buy them a few extra days, but that won't be enough.

Even ace Dallas Keuchel is on pace to have a career-high workload, He's thrown a Major League-leading 124 1/3 innings in 17 starts after posting a career-high 200 innings last year. The Astros have used 11 different starting pitchers this year, which equals their total from 2014.

• Astros reliever Chad Qualls, who's been on the disabled list for a week with a pinched nerve in his neck, is scheduled to begin a rehab assignment with Double-A Corpus Christi in the coming days. Manager A.J. Hinch said: "We've solved the pain he was having."