EAGAN, Minn. – The Vikings released their initial 53-man roster Tuesday, but don't go etching that lineup in stone.

Vikings Head Coach Mike Zimmer told media members Wednesday to expect further changes.

"As far as the roster cuts, everything is still very fluid, so what you see right now probably isn't going to be the ending roster," Zimmer said.

Among other potential moves, Minnesota will need to make space for tight end Chris Herndon, whom the team acquired from the Jets via trade. That likely will come in the form of moving Irv Smith, Jr., to Injured Reserve after the third-year tight end underwent surgery to repair a meniscus injury Wednesday morning.

"We knew it was probably going to be a little while anyway. Those are all part of things you have to plan for," Zimmer said.

Whether or not any other players rehabbing injuries will be moved to IR remains to be seen.

Defensive end Everson Griffen was included in Tuesday's wave of cuts, but the Vikings haven't completely closed the door on a return for the veteran who recently re-joined the team.

"We'll see," Zimmer said when asked about bringing Griffen back.

Another position to keep an eye on is quarterback.

As of Tuesday's roster unveiling, Minnesota retained just two QBs: Kirk Cousins and rookie Kellen Mond. The team released Nate Stanley and Jake Browning.

Zimmer fielded a question about whether he's comfortable with establishing Mond as Cousins' direct backup.

"Umm, right now," Zimmer said. "We'll see what happens in the next few days. Like I said, everything is fluid."

The head coach did acknowledge Mond's improvement after returning from a COVID-19 quarantine.

"I think he's gotten better the last two or three games," Zimmer said. "He's doing a good job with the playbook. Made some good throws. Made some mistakes, like most rookies do. We'll see. We have to keep getting him better."

In addition to a fluctuating roster, the Vikings game plan and how they utilize players at certain positions also remains indefinite.

One example is how Smith's absence will impact Minnesota's offensive approach.

With Smith out, Zimmer noted, it doesn't necessarily mean Tyler Conklin or Herndon will be asked to fill the exact role of their peer.

"It's really not so much about 'roles,' " Zimmer explained. "It's really about – Conklin is a good player – using these guys to their abilities.

"It may be we were planning on using Irv a little more on third down as a slot receiver. Probably won't do that now," he added. "Probably go with three wides. Some of those things, we'll have to adapt and change."