Donald Penn suffered a groin injury in the Raiders’ overtime win over the Browns and will head to IR as a result, Ian Rapoport and MJ Acosta of NFL.com report (on Twitter).

The team does not view this as a season-ending malady, Rapoport adds, and Jon Gruden confirmed as such. Penn would be able to return in eight weeks.

The Raiders are turning to another team’s practice squad to replace Penn on the roster. They’re signing tackle Ian Silberman off the Titans’ practice squad, Paul Gutierrez of ESPN.com reports. Silberman went to the past two Raiders training camps and started at right tackle during part of the preseason. He made the team out of camp but was waived before Week 1.

Second-round pick Brandon Parker will start at right tackle on Sunday, according to The Athletic’s Vic Tafur (on Twitter), giving Oakland two rookie tackle starters flanking three proven veterans inside. Parker’s played 57 snaps this season. Penn has logged 188 at his new position, but, at least in the view of Pro Football Focus, the transition from left to right tackle has not gone well. Penn’s graded as the league’s worst full-time tackle, per PFF.

Nevertheless, the Raiders hope he can be an IR-return candidate. Penn’s profile would suggest as much. This has been another interesting year for the veteran blocker. He was the subject of trade rumors coming into the season, and the 35-year-old tackle was moved off the left side — where Kolton Miller now resides — for the first time in his 11-year NFL career. This occurred despite Penn making the past two Pro Bowls.

This injury will represent the most time Penn has missed as an NFLer as well. Prior to last season, when he played 14 games, Penn had suited up for every game of his career.