Would you rather spend more on a WR in free agency - like Landry for 3-4 years? Or do you think Colts should resign Moncrief for 1-2 years? #coltsmail — Richard Bilbee (@richardbilbee) February 2, 2018

@MikeWellsNFL: Of all the mysteries -- and there have been quite a few of late -- when it comes to the Indianapolis Colts, receiver Donte Moncrief is one of the biggest. Moncrief had all the tools -- size, strength, speed -- to be the Colts' best all-around receiver the past few seasons, but things never came together for him for a number of reasons.

Moncrief, 24, spent the past two seasons dealing with injuries. He missed seven games in 2016 due to a shoulder injury, then missed the final four of 2017 with an ankle injury. He had just 84 more receiving yards this season than he did in 2016 despite playing three more games. Part of that problem was that the Colts had Jacoby Brissett at quarterback. Brissett, acquired a week before the start of the regular season, developed a comfort level with receiver T.Y. Hilton and tight end Jack Doyle in the offense.

But Moncrief -- a third-round pick in 2014 -- didn’t take advantage of the opportunities given to him, either, last season. He went from being a lock to be the No. 2 receiver behind Hilton to losing that spot to Kamar Aiken, posting a career-low 26 receptions.

Moncrief’s up-and-down play had many inside the organization frustrated, which is easily understood when you look at his skill set. If the Colts offer Moncrief a contract, I wouldn’t be surprised if it’s a short-term deal where the receiver has to prove his value. Hilton and Chester Rogers are the only two receivers with much experience under contract for the Colts for 2018.

That brings us to the free-agent market. The Colts will have close to $85 million in salary-cap space, but do not expect general manager Chris Ballard to act like he’s Christmas shopping and spend freely. He’ll continue to be diligent, particularly since it’s not an overly strong receiving class.

Miami’s Jarvis Landry appears to be the best receiver on the market. He’s had at least 1,100 yards receiving and 110 receptions in two of the plast three seasons. And at age 25, Landry has plenty of good years ahead of him.

Other notable free-agent receivers include Sammy Watkins of the Los Angeles Rams and Jacksonville’s Allen Robinson and Marqise Lee.

This free-agent class is part of the reason why you can’t shut the door on a potential Moncrief return.