Matt Olson returns to A’s lineup after thumb injury

Three days after taking a 90 mile-per-hour fastball off his left thumb, A’s first baseman Matt Olson returned to the starting lineup Thursday for the first contest of Oakland’s four-game homestand against the Detroit Tigers, a significant development with his team looking to extend its winning streak to five games.

The 27-year-old corner infielder was diagnosed with a thumb contusion after he was hit by a pitch Monday in the top of the seventh inning of the A’s 9-5 win over the Arizona Diamondbacks. According to manager Bob Melvin, Olson’s thumb immediately swelled, prompting his removal from the game. X-rays came back negative.

Although no bones were broken, Melvin told reporters the next day that the swelling on Olson’s thumb had not subsided. Melvin said it was “difficult for him to grip a bat let alone really even catch a ball.” He’s made significant progress since then.

“Based on what I saw the other day I was a little bit unsure,” Melvin said. “Today he let me know before he even grabbed a bat that he was going to play.

“He’s a tough guy.”

Olson isn’t the only A’s player who made noteworthy progress after an injury.

Outfielder Chad Pinder, who hit .300 with a home run and two RBIs in four games to start the season, sprained his left knee when he crashed into the padded right-field wall on April 4 in the A’s opening series finale against the Houston Astros. He was subsequently shut down in order to aid his recovery,

Melvin said Thursday that Pinder should start baseball activities this week and pending how his body responds to that, he could start running soon after.

“He could start swinging the bat in the next couple of days,” Melvin said. “Still not sure on a timetable, but once you start baseball activity, you’re feeling good enough to get the process going.”

Left-handed pitcher A.J. Puk (biceps) is back to throwing from 90 feet. Since he was placed on the injured list on April 8, Puk has thrown twice, Melvin said. There is still no timetable for Puk’s return.

“Based on the fact that he’s throwing now, it means he’s starting what he needs to do to try and get ready again,” Melvin said. “With pitchers, it takes some time. They’re going to have to throw some bullpens and throw to hitters and so forth and so on. We’re not anywhere close yet.”

Though it likely has less to do with his sore hamstring and more with the fact that the Tigers are starting left-handed pitcher Tarik Skubal, a Hayward native whose family moved out of state when was in sixth grade, A’s 35-year-old designated hitter Mitch Moreland is still absent from Oakland’s starting lineup. He hasn’t started a game since April 8.

Should Moreland and Olson be unable to play on a given day, utility player Seth Brown has filled in admirably at first base. Brown has been primarily an outfielder in his parts of three seasons with the A’s.

Brown hit the go-ahead home run in the top of the eighth inning of the A’s 7-5 win over Arizona on Tuesday, his second long ball of the year. The 28-year-old has impressed Melvin.

“He’s starting to feel comfortable here and he should,” Melvin said. “He’s doing a nice job for us.”