Franks completed 5 of 9 passes for 75 yards against the Michigan Wolverines last week before being pulled in the third quarter after losing a fumble while trying to scramble for a first down.
Notre Dame grad transfer Malik Zaire replaced Franks and completed 9 of 17 passes for 106 yards in the 33-17 loss in the AdvoCare Classic in Arlington, Texas.
"Both guys did some good things and both guys did some things they obviously want back," McElwain said.
Franks will remain the starter Saturday for No. 22 Florida's home opener against FCS school Northern Colorado, which beat visiting College of Idaho 41-14 in its season opener.
Franks connected on a 34-yard pass play on the game's second snap but the rest of his performance was uneven. McElwain noted that Zaire sometimes bailed out of the pocket too quickly.
"It's something he's got to get better at," McElwain said.
Junior Luke Del Rio, who started six games last season, is a third option. McElwain said he had planned to use Del Rio last week if the Gators were in a two-minute drill.
For Northern Colorado, junior quarterback Jacob Knipp helped the Bears score 28 first-quarter points en route to their easy victory last week. Running back Trae Riek ran 18 times for a team-high 71 yards and three touchdowns -- all the scores coming in the first quarter.
Two of the first-period touchdowns were set up by interceptions.
"We knew we had to be a little more aggressive," said Northern Colorado coach Earnest Collins, whose team went 6-5 last season. "Until our offense gets it going and our O-line gets a few more games under its belt, we have to be aggressive on defense. So we have to hold them on the back end and put a little more pressure on the quarterback up front."
Florida has won the past two Southeastern Conference East titles but had been hoping the offense would take a positive turn in McElwain's third season as head coach. But the Gators managed only 192 yards of total offense -- including 11 on the ground -- in the loss to the Wolverines.
Florida failed to score an offensive touchdown, with 14 of their points coming on interception returns for touchdowns by cornerbacks Duke Dawson and C.J. Henderson.
"One thing I want you to know is I believe in these guys," McElwain said. "They believe in themselves. We've made corrections."
One of those "corrections" will not be who calls plays. Offensive coordinator Doug Nussmeier was a big target on social media after the game, but McElwain said he didn't see play-calling as an issue. Nussmeier will continue to call the plays against Northern Colorado.
"I've seen what he can do. I've seen what he's done," McElwain said. "Getting the people the ball with the ability to make plays, that's the biggest piece of it. We'll continue to work at it."
Ultimately, McElwain blamed the loss on the inability to physically handle Michigan. Florida's offensive line was unable to protect the quarterback, allowing six sacks. The Gators were out-rushed 215-11.
The status of leading running back Jordan Scarlett (889 yards last season) and leading receiver Antonio Callaway (721 yards receiving last season) remain in question. Both were among 10 players suspended for the Michigan game due to their role in a debit card fraud scheme that's still under investigation.
Neither Scarlett nor Callaway were on the depth chart released Tuesday by Florida.
Gators starting safety Chauncey Gardner II underwent an MRI after suffering a leg injury last week. His status was expected to be updated Wednesday.
Knipp completed 17 of 27 passes for 238 yards last week against College of Idaho. It was his first game action since suffering a shoulder injury in the second game of last season.
"He commanded the offense," Collins said.
"He had some overthrows. He had some underthrows, but that's the rust. He'll get the film. He's a studier of the film, and he'll get in there and look at it and see what his footwork was like, why he was over on the overthrows, why he was under on the underthrows. He'll get it fixed."
Bears kicker Collin Root was chosen the Big Sky Conference's player of the week after setting a school record with a 56-yard field goal.