The San Francisco 49ers may be without the services of Pro Bowl tight end Vernon Davis while  he holds out for a new contract.

The 49ers’ other tight ends were told not to expect to see Davis at the team’s voluntary offseason workouts in the near future, Matt Maiocco of Comcast SportsNet Bay Area reports. Eric Mangini,  a former head coach who will serve as the 49ers’ new tight ends coach this season, told the team’s other players to use Davis’ absence as an opportunity to compete for playing time.

Still, Vance McDonald, a second-year player out of Rice University and Davis’ immediate backup, said that his absence is hard to ignore. “It’s different,” he told reporters. “He’s goofy and goofing off, but when it comes to football he’s always full-tilt. I miss the dude. I’ll be honest. I miss the dude.”

Davis, 30, signed a five-year, $36.75 million contract extension in 2010, and is slated to earn about $4.98 million in base salary and bonuses in 2014. He’s already the third-highest paid tight end in the NFL, but he will reportedly seek a raise.

By skipping the 49ers’ offseason program, Davis will forfeit a $200,000 workout bonus. He’ll also be subject to fines if his holdout extends into the 49ers’ obligatory minicamp, which begins in mid-June, reports.

But Davis isn’t the only 49ers player who is unhappy with his contact. ESPN’s Bill Williamson identifies offensive guard Alex Boone as another player who may opt to holdout for a new deal ahead of the 2014 NFL season.

Meanwhile, the 49ers and franchise quarterback Colin Kaepernick agreed to terms on a six-year, $126 million contract on Wednesday, $61 million of which is guaranteed. The deal makes Kaepernick the most expensive quarterback in NFL history.