Deichmann signed a minor-league contract Thursday with the Athletics, Melissa Lockard of The Athletic reports.
The Cubs released Deichmann on Monday.
Deichmann was designated for assignment on Saturday, Sahadev Sharma of The Athletic reports.
Deichmann was optioned to Triple-A Iowa on Friday.
Deichmann could see some playing time this season as a left-handed bench option in the outfield, Sahadev Sharma of The Athletic reports.
Deichmann was recalled by the Cubs on Friday, Jordan Bastian of MLB.com reports.
Deichmann was optioned to Triple-A Iowa on Sunday, Maddie Lee of NBC Sports Chicago reports.
Deichmann is starting in right field and batting fifth in Monday's game against the Brewers.
Deichmann isn't starting Saturday's game against the White Sox.
Deichmann was recalled by the Cubs on Friday and will bat fifth and play right field against the White Sox in his major-league debut.