If the New England Patriots want to acquire a legitimate insurance policy for Rob Gronkowski in free agency, their options are running out.

The New Orleans Saints are expected to sign free-agent tight end Jared Cook, NFL Media's Ian Rapoport reported Thursday morning.

Cook turns 32 in April but arguably was the best free agent tight end left on the market; he posted career highs in receptions (68), receiving yards (896) and touchdowns (6) for the Oakland Raiders in 2018 while making his first Pro Bowl.

Cook joins big names like Tyler Eifert, Jesse James and Tyler Kroft who have either re-signed with their clubs or joined new teams. So, who's still out there? Here's an updated look at the some of the top remaining free-agent tight ends still available:

- Austin Seferian-Jenkins (last team: Jaguars)

- James O'Shaughnessy (Jaguars)

- A.J. Derby (Dolphins)

- Jermaine Gresham (Cardinals)

- Neal Sterling (Jets)

- Maxx Williams (Ravens)

- Levine Toilolo (Lions)

Translation: It's slim pickings out there.

The Patriots did acquire a tight end in free agency, signing 26-year-old Matt LaCosse from the Denver Broncos. After Dwayne Allen's departure, though, LaCosse and Jacob Hollister don't inspire much confidence as New England's tight end depth chart behind Gronkowski, who hasn't even confirmed he's playing in 2019.

That would suggest the Patriots may seek tight end depth via trade or the 2019 NFL Draft, where several quality prospects could fall to Bill Belichick's club at No. 32 overall.

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