OAKLAND -- Matt Chapman was back in action with the A's on Monday, coming off the disabled list following an unexpected hospital stay for a left knee infection that developed just four days into his big league career.
The rookie third baseman, whose return led the A's to option first baseman/outfielder Matt Olson to Triple-A Nashville, hit second in Oakland's series-opening matchup with the White Sox.
"You don't want too much pressure on a younger guy, but he was pretty impactful in the four games he was here for us," A's manager Bob Melvin said. "He certainly makes our defense better right away and had some good at-bats for us. At this point, anybody we can get back among the guys on the DL will be good for us, and it's nice to have him back."
Chapman, 24, was promoted from Triple-A on June 15 for his big league debut and went 3-for-14 with three RBIs in a four-game set against the Yankees, before succumbing to the knee infection. He spent three nights in the hospital, receiving antibiotics through an IV.
Chapman played in a pair of rehab games with Class A Advanced Stockton on Saturday and Sunday, finishing 0-for-7.
"I feel good," Chapman said. "It feels like my debut all over again. Just excited to get back out there with my teammates and help the team win."
Monday marked the first time the A's had both of their top two position prospects in their lineup; Chapman, ranked by MLB Pipeline as the organization's No. 4 prospect, was joined by second baseman Franklin Barreto, ranked second.
"He's a great player and somebody that I've played with three years in a row now, so somebody that I'm close to and respect and appreciate the game," Chapman said, "so it's nice to be back out there with some familiar faces."
Olson was 9-for-40 with four home runs in 10 games during his fourth stint with Oakland, spending the majority of his time in right field.
"I thought he did well," Melvin said. "The average doesn't look great, but he got some big hits for us, had some big at-bats. We feel he's in the future our guy at first base and does a great job there but filled in nicely at right field."
Worth noting
• Corner infielder Ryon Healy, who exited Sunday's game with upper back spasms, was out of the lineup Monday but was feeling "a little better," per Melvin. Healy remains day to day.
• Right-hander Kendall Graveman (shoulder) threw a 30-pitch bullpen session at the Coliseum on Monday. He'll travel to Arizona this week for an extended bullpen and is on track to face hitters soon.