The Seahawks are finalizing a trade to send tight end Nick Vannett to the Steelers, a league source told ESPN's Adam Schefter.

The Seahawks will receive a 2020 fifth-round pick in the deal, the source said.

Steelers starting tight end Vance McDonald hurt his shoulder early in Sunday's loss in San Francisco, and his shoulder was in a sling Tuesday, but as for how long he could miss, a source told Schefter, "Not long." His status for Week 4 on Monday night against the Bengals hasn't been announced by the team.

Vannett will join a tight end group in Pittsburgh that includes Xavier Grimble and Zach Gentry. The team also signed Alizé Mack to its practice squad Tuesday.

Vannett was a third-round pick in 2016 out of Ohio State and is in the final year of his rookie contract. He's caught 48 passes for 463 yards and four touchdowns in 42 regular-season games. His best season was 2018 with 29 catches for 269 yards and three touchdowns.

Vannett has been the Seahawks' No. 2 tight end this season behind Will Dissly, who is now the only true tight end on their 53-man roster. However, backup tackle George Fant is a de facto tight end. Seattle also has Jacob Hollister on its practice squad. Veteran Ed Dickson is eligible to return off injured reserve in Week 9.

The addition of Pittsburgh's fifth-rounder gives the Seahawks 10 picks in the 2020 draft, including the four compensatory selections they're projected to receive.

ESPN's Brady Henderson contributed to this report.