ALLEN PARK, Mich. (AP) -- The Detroit Lions have invested a lot in their offensive line the last two years, drafting prospects and signing veterans.
Detroit's plans to bolster the critical unit just sustained a setback.
Left tackle Taylor Decker has had shoulder surgery and is out indefinitely.
''He's on the road to recovery,'' Lions coach Jim Caldwell said Tuesday.
And Caldwell doesn't know, or won't say, how long it will take to get Decker back on the field. Caldwell said he didn't think the surgery would end Decker's 2017 season.
''Not certain,'' he insisted. ''We'll probably give you an update when we get back to training camp.''
The Lions will report to training camp in late July.
Caldwell said Decker was injured last week during an offseason workout, but declined to say how it happened. He also defended the team's routines, which he said has been witnessed by NFL Players Association among others.
''We've never been cited,'' he said. ''We've never had an issue in that regard. We comply by the rules, but things happen sometimes in practice. Just the nature of business.''
To protect quarterback Matthew Stafford, and improve a lackluster running game, Detroit drafted Decker No. 16 overall in 2016, and he started every game without missing a snap on offense. The Lions also drafted Graham Glasgow in the third round last year and he started 11 games, mostly at guard with some at center, and selected Joe Dahl in the fifth round in 2016 to add depth. And to replace departing free agents Riley Reiff and Larry Warford, veterans Rick Wagner and T.J. Lang were signed this offseason.
Depending on how long Decker will be out, the Lions might sign another tackle such as free agents King Dunlap or Ryan Clady.
''We're always looking at options throughout the weeks, throughout the days to improve our team,'' Caldwell said. ''And, we certainly don't rule that out.''
Wagner was signed to play right tackle, but Caldwell said he's capable of playing left tackle.
The Lions opened their workout Tuesday for the media, giving a glimpse at their plans to at least temporarily replace Decker at a pivotal position. They put Dahl and Cornelius Lucas at left tackle for some snaps with the No. 1 offense.
''We're going to get reps for everybody, everywhere,'' offensive coordinator Jim Bob Cooter said. ''And really make sure we evaluate the situation pretty in depth.''
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