Quintana was designated for assignment by the Giants on Thursday.
Quintana allowed five earned runs with a 12:6 K:BB over 9.2 innings since being claimed off waivers by the Giants in August, and he's now been removed from the 40-man roster with four games left in the regular season. It's been a disaster of a 2021 campaign for the veteran left-hander, who started the year with the Angels and posted a 6.75 ERA, 1.78 WHIP and 73:29 K:BB across 53.1 innings before being let go and joining the Giants.