Extra bases

Extra bases

• Chris Volstad got a win. The right-hander, sent to Triple-A Iowa after opening the season 0-6 in eight starts, won Tuesday for Iowa. He gave up four runs on seven hits over six innings in the Iowa Cubs' 18-8 victory over Tacoma. Volstad hasn't gotten that kind of run support in his last 18 starts in the big leagues. His teams have averaged 2.66 runs while he's on the mound in that stretch.

Anthony Rizzo had three hits for the Iowa Cubs, including his 15th home run, and now has 42 RBIs for the season.

• Cubs manager Dale Sveum will miss Wednesday's game to attend his son, Rustin's, high school graduation from Desert Mountain High School in Scottsdale, Ariz.

It's an evening ceremony, so Sveum won't be able to watch the Cubs' series finale against the Astros.

"He'll be graduating, so most of that time, I'll be looking at my phone [for updates]," Sveum said.

Bench coach Jamie Quirk will take over on Wednesday.

• Reliever Blake Parker, bothered by a tight right hamstring, was able to throw on flat ground Tuesday but will only be used in emergency, Sveum said. Parker has not pitched since Saturday.