The Athletics could elect to wait until Wednesday to officially promote Kurtz from Triple-A Las Vegas with the team scheduled to face left-handed starter Patrick Corbin in Tuesday's game against the Rangers, Martin Gallegos of MLB.com reports.

Reports surfaced earlier Monday indicating that Kurtz was set to join the big club, but the 22-year-old looks like he'll end up waiting a couple more days before making his MLB debut. Kurtz earned his spot on the big-league roster after slashing .321/.385/.655 with seven home runs over 96 plate appearances with Las Vegas to begin the season.

Schmitt has been diagnosed with a Grade 2 oblique strain and is expected to miss one month, Alex Pavlovic of NBC Sports Bay Area reports.

Schmitt was officially placed on the 10-day injured list Saturday, though the extent of the injury wasn't truly known until Monday when he underwent an MRI. This news confirms that he'll miss more than the 10-day minimum and is looking at a potential return in mid-to-late May.

Walker is not in the lineup for Monday's game against the Blue Jays.

Walker hit his second home run of the season this past weekend against the Padres, but he's just 3-for-26 across his last eight contests and is slashing only .156/.253/.260 on the season. Zach Dezenzo is at first base and hitting ninth for the Astros.

The Athletics are set to promote Kurtz from Triple-A Las Vegas prior to Tuesday's game against the Rangers, Martin Gallegos of MLB.com reports.

The No. 4 overall pick in the 2024 First-Year Player Draft, Kurtz has slashed a robust .321/.385/.655 with seven home runs with Las Vegas this season and will make his major-league debut after racing through the minors. Kurtz is likely to split time between designated hitter and first base with Tyler Soderstrom, resulting in Brent Rooker seeing more starts in left field.

Arraez (concussion) is expected to be placed on the 7-day injured list prior to Monday's game against the Tigers, Kevin Acee of The San Diego Union-Tribune reports.

Arraez is dealing with concussion symptoms after colliding with the Astros' Mauricio Dubon on Sunday. The infielder was taken off the field on a stretcher following the concussion and was sent to a local hospital for further evaluation. He's since posted on social media that he's feeling fine physically, but Arraez will be out for at least one week while he waits for his concussion symptoms to subside. Connor Joe, Yuli Gurriel and Gavin Sheets will be the main candidates to see playing time at first base in Arraez's absence.

Vaughn is absent from the lineup for Monday's game in Boston.

It's a day off for Vaughn, who had started every game since April 4. Nick Maton is covering first base and batting leadoff for the White Sox, while Andrew Benintendi is getting at start at designated hitter.

Horwitz (wrist) has been cleared for baseball activity and will participate in extended spring training, MLB.com reports.

This marks a significant step in Horwitz's recovery, though he'll still likely need plenty of ramp-up time after missing all of spring training. He should take over as Pittsburgh's primary first baseman once activated from the injured list.

Valdez (shoulder) went 0-for-2 with a walk and a run scored Sunday against the Guardians.

Valdez was out of the starting lineup after suffering a minor shoulder injury Saturday, though he managed to enter the game as a pinch hitter in the sixth inning. That suggests Valdez should avoid a stint on the injured list, but his status will likely remain unclear until the Pirates retake the field Tuesday.

Lowe combined to go 4-for-7 with an RBI and a walk during Sunday's doubleheader against the Rockies.

Lowe went 1-for-3 with a walk during the Game 1 victory and followed that up with a 3-for-4 performance during a loss in the second game. He's collected multiple hits in three of his last six games after going 5-for-29 (.172) over his previous nine appearances. Lowe is now slashing .295/.375/.474 with 17 RBI through 22 games.

Olson went 1-for-3 with a two-run home run in Sunday's 6-2 win over the Twins.

Olson opened the scoring with a two-run blast off Joe Ryan in the first inning. The first baseman has picked things up over his last 10 games, hitting safely in eight of them while driving in eight runs. On the season, he's slashing .233/.371/.411 with three homers, 13 RBI and seven runs scored across 89 plate appearances.