It is not going to happen.
New England did not activate Mitchell to its 53-man roster on Friday, per the NFL transaction wire, and as a result he will not be eligible to play Saturday.
Mitchell has missed the entire season after being placed on injured reserve with a knee injury before the regular-season opener.
The notion that Mitchell would play this weekend lost some steam when he missed practice on Tuesday and Wednesday. He did participate in the team's walk-through on Thursday, but apparently is not ready to play in a game.
Last season, Mitchell had 32 receptions for 401 yards and four touchdowns in 14 regular-season games, including six starts.