Redskins Coach Jay Gruden filled the last big hole on his staff by hiring Tim Rattay as quarterbacks coach. (John McDonnell/The Washington Post)

The Washington Redskins filled an important hole on their coaching staff Friday by hiring Tim Rattay as their quarterbacks coach. The bigger question is: Whom will he be coaching?

Washington is actively searching for a quarterback either through free agency or the draft, several people with knowledge of the team’s plans said, as the reality sets in that Alex Smith might never return. Smith suffered a compound leg fracture in November, then endured a further setback when the leg became infected. Team executives, including President Bruce Allen, say they hope Smith will return in 2019, but they are planning for the possibility that he’ll never be back.

This makes the Rattay hire a critical one. Coach Jay Gruden interviewed a handful of candidates, including former Cincinnati Bengals offensive coordinator Ken Zampese, after promoting passing game coordinator Kevin O’Connell to offensive coordinator late last month. Like Smith, the 41-year-old Rattay is a former 49ers quarterback. He later played a season for the Tampa Bay Buccaneers when Gruden was an offensive assistant there.

After his playing career, Rattay coached wide receivers for the United Football League’s Las Vegas Locomotives before taking a similar position at Louisiana Tech in 2013. He spent the past four seasons coaching quarterbacks at Louisiana Tech and helped develop Bengals backup Jeff Driskel.

Rattay becomes the fourth coach on the Redskins with quarterback coaching experience, joining Gruden, O’Connell and senior offensive assistant Matt Cavanaugh. All will contribute to coaching Colt McCoy, Josh Johnson — who has been talking to the team about a contract — and whatever quarterback Washington drafts or signs in free agency. Rattay, though, will be the one who spends the most time with those passers.

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