Earlier today, New England Patriots tight end Rob Gronkowski announced his retirement from the NFL — a decision that ends one of the greatest careers in league history, and leaves the reigning world champions with a gigantic hole to fill. After all, Gronkowski was one of the league’s toughest matchups and outstanding as a receiver and a blocker; a pure tight end elite in every aspect of playing the position.

Naturally, the Patriots will not be able to replace the 29-year-old one-for-one. Instead, it will likely take a group effort to do that and a look at the current tight end group shows that the team and its coaching staff has its work cut out for it:

New England currently has four tight ends on its roster, and they combine for 76 games of experience — for comparison, Gronkowski ends his career having appeared in 131 NFL contests. Experience, however, is possibly the least of the problems when it comes to a group that is now without its premier pass catcher and blocker.

Jacob Hollister and Stephen Anderson are expected to help fill the former of the two roles: both are better suited as receivers and have some decent albeit unspectacular production on their respective résumés. Hollister, who joined the Patriots in 2017 as an undrafted rookie free agent, has caught nine passes for 94 yards in his career. Anderson, on the other hand, has caught 36 passes for 435 yards and two touchdowns while he was still with the Houston Texans in 2016 and 2017.

Free agency acquisition Matt LaCosse and 2018 seventh-round draft pick Ryan Izzo, on the other hand, are projected to help fill the void of Gronkowski’s outstanding blocking. LaCosse, who was stuck near the bottom of the depth chart with both the New York Giants and the Denver Broncos, is the favorite to win the role while Izzo is a wild card: he has the frame to be successful as a blocking tight end but has yet to prove his value.

Of course, the Patriots can and likely will invest in a tight end during the draft. Iowa’s T.J. Hockenson is the player most resembling Gronkowski as an all-around tight end, while his college teammate Noah Fant is more of a receiver but brings tremendous athletic upside to the table. Both would be first-round options, with Alabama’s Irv Smith Jr. and Texas A&M’s Jace Sternberger possible round-two targets.