Phillips turned in a career season in 2019, finishing second among all defensive tackles with 9.5 sacks. He was claimed by the Bills in 2018 after being released by the Dolphins following a sideline outburst regarding his playing time.
Nkemdiche was released in July after he reported to training camp out of shape. He was later signed by the Dolphins and was released after being suspended for two weeks by the NFL.
Philon, who had signed as a free agent last March, was released in August after he was arrested on charges of aggravated assault with a deadly weapon.
Both players were expected to play significant snaps in 2019.
Those two decisions left the Cardinals with a limited rotation up front, as Arizona finished the season with 40 sacks -- 19 by outside linebacker Chandler Jones. Only seven sacks came from players on defensive line.
Although Buffalo drafted defensive tackle Ed Oliver in the first round of the 2019 draft, the team signed Phillips to a one-year extension last offseason, and Phillips briefly overtook Oliver in the starting lineup midway through the season.
Phillips has 15 sacks in his five-year career to go along with 111 tackles, 14 pass deflections and 27 tackles for loss.
ESPN's Marcel Louis-Jacques and Josh Weinfuss contributed to this report.