The Vikings’ $11 million investment in inconsistent left tackle Matt Kalil last spring was not without risks. Still, coach Mike Zimmer liked the early results from a preseason spent tweaking Kalil’s footwork in pass protection.

Then Kalil injured a hip in practice, starting the left tackle who’d never missed a snap down a path leading to surgery and 14 games on injured reserve. The Vikings’ hefty bet on Kalil, via last year’s expensive fifth-year option on his rookie contract, fell flat in an attempt to make one more evaluation on him.

Now the Vikings have a hole at left tackle with no heir apparent on the 2017 roster. So where does that leave Kalil, a pending free agent with a history of knee issues? And where does it leave the Vikings?

An improved running game and a more explosive passing game top the Vikings’ priority list on offense, coordinator Pat Shurmur said last week at the team’s WinterFest in Prior Lake. How the Vikings achieve that undoubtedly will start along last year’s tattered offensive line. Shurmur declined to get into specifics about Kalil.

“Certainly anything you do on offense starts up front,” Shurmur said. “So obviously there will be changes at all the position groups.”

What’s clear is the Vikings’ need at tackle is dire.

They face a draft with little fanfare at the position, and the reality is that proven left tackles don’t often become available in free agency.

Cincinnati’s Andrew Whitworth, ahead of his age-35 season, looks as if he’s the market’s top option, should he even reach free agency as the Bengals reportedly sought to discuss a new deal with him recently. Denver’s Russell Okung is another veteran under contract who could be made available in March. Miami’s Brandon Albert was in that category, but the Dolphins agreed to trade him to Jacksonville on Monday. Trades can’t be made official until the new league year begins March 9.

The Vikings have had a propensity under General Manager Rick Spielman to bet on the known over the unknown by keeping many deals — whether lucrative extensions or prove-it contracts — for their own players.

What that means for Kalil’s future in Minnesota is uncertain, but a possible return might not be as far-fetched as it once seemed.

Pending free-agent left tackles


Andrew Whitworth (Bengals), age 35: Even though Whitworth turned 35 in December, the Bengals tackle is coming off perhaps his best seasons in the past two years, which include two Pro Bowls and a first-team All-Pro selection. Whitworth hasn’t missed a game since 2013 and has sat out only eight games in his 11-year career.

Riley Reiff (Lions), 28: A lackluster left tackle market could have some thinking about Reiff moving back to where he started 47 of 48 games for the Lions from 2013 to 2015. Detroit moved Reiff to right tackle last season following the first-round selection of Taylor Decker. Reiff has missed only three starts in the past four seasons.

Ty Nsekhe (Redskins), 31: The Vikings saw firsthand Nsekhe’s play at left tackle when Everson Griffen went without a sack in their Nov. 13 meeting. Nsekhe, a 31-year-old journeyman, has only six career starts, but he made a strong case in four of them last season during Trent Williams’ suspension. Nsekhe was active for 16 games last season while dealing with a nagging ankle injury.

Kelvin Beachum (Jaguars), 27: Unlike he did against Nsekhe, the Vikings’ Griffen had little trouble breezing past Beachum in Jacksonville last season. The game exemplified a down season for Beachum, a former seventh-round pick by the Steelers. He’s just a year removed from a torn ACL, which ended his run as a starter in Pittsburgh, and could be worth a look for the tackle-needy Vikings.

Ryan Clady (Jets), 30: The former All-Pro left tackle for the Broncos has had tough luck the past four seasons, starting 16 games only once. Clady appeared in nine games with the Jets before a torn rotator cuff landed him on injured reserve. The Jets declined Clady’s 2017 option, so he’s a free agent. Clady has missed 37 games because of foot, ACL and shoulder injuries the past four seasons.

Also: William Beatty (Giants), Ben Ijalana (Jets), Bradley Sowell (Seahawks).