Detroit Lions sign former AAF quarterback Luis Perez, release David Fales

The Detroit Lions are adding another quarterback to their backup mix, or at least bringing one in to keep around on the practice squad this fall.

The Lions signed former Alliance of American Football quarterback Luis Perez on Tuesday and released David Fales.

"It’s someone that we’ve actually tracked here for a little while and had kind of on our radar," Lions coach Matt Patricia said. "We don’t have a lot of time left in the preseason so if we’re going to have a chance to take a look at somebody we got to do it and just made the decision, which we did. He’ll be thrown into the mix."

Perez signed with the Los Angeles Rams as an undrafted rookie last year and spent part of this spring with the Philadelphia Eagles after playing for the Birmingham Iron of the AAF. The AAF suspended operations in the spring, after Perez threw for 1,460 yards and five touchdowns with six interceptions in seven starts.

The Lions have three other quarterbacks currently on their roster, starter Matthew Stafford and backups Tom Savage and Josh Johnson, but need a quarterback to man their practice squad for the season.

With only one of Savage and Johnson likely to be kept on the 53-man roster, Perez should be the third, developmental quarterback this fall.

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Stafford completed 12 of 19 passes for 137 yards in his only action of the preseason last week against the Buffalo Bills. He's not expected to play in Thursday's preseason finale against the Cleveland Browns.

"Tough to judge where (the offense) is, where it’s going to be, all of that," Stafford said last week. "I just know we’re always trying to be better."

Fales was 20 of 41 passing for 310 yards with one touchdown and one interception this summer.

Contact Dave Birkett at dbirkett@freepress.com. Follow him on Twitter @davebirkett. Read more on the Detroit Lions and sign up for our Lions newsletter.