Buffalo's mandatory minicamp will get underway on Tuesday this week. They will be the final three practice sessions for the Bills before they take their five week break prior to training camp.

There are some elements in all three phases of the team's game that need to be sharpened or refined as the coaches try to get a clearer picture of just what they have on their roster heading into the final phase of preparations at St. John Fisher for the 2015 season.

Here's a look at some of the more pressing items on that list.

1. Quarterback-receiver chemistry

This was expected to be a work in progress. With everyone learning a new scheme the players have been primarily focused on the execution of their individual assignments during the installation process. Working with three different quarterbacks, who are rotating time under center with the first unit, has also lengthened the time it might take for the receivers and tight ends to develop chemistry with any one of the signal callers.

Mandatory minicamp might be the first real opportunity for some of the on field chemistry in the passing game to begin to develop.

2. Linebacker depth

On defense the starting 11 is a stacked group. There's also little doubt about the depth at defensive line and in the secondary. Linebacker however, is another story. Buffalo's projected starters at linebacker are all proven players in Nigel Bradham, Preston Brown and Manny Lawson. Ty Powell, who is Brown's direct understudy and potential interior partner in 3-4 fronts, has been getting rave reviews from the coaching staff. Beyond that there is a lot of unproven talent that needs to show they're capable of stepping up if called upon to step into the lineup this fall.

The key names among the second wave of linebackers include Jimmy Gaines, Randell Johnson and the aforementioned Powell.

3. Offensive tackle battle?

Buffalo's coaching staff has been impressed with Cordy Glenn's fitness level and performance this spring, which essentially makes him a lock as the incumbent at left tackle. That likely leaves Seantrel Henderson and Cyrus Kouandjio in a two-man battle for the starting right tackle job.

Kouandjio has seen significantly more time at right tackle in the OTA sessions with the first unit than Henderson. The Miami product has been working more at left tackle with the second unit through the spring.

In this mandatory minicamp it will be interesting to see if the approach changes with the pair of second-year tackles and whether they'll be pitted directly against one another for a starting role.

4. Return from rehab?

A handful of projected starters have been working their way back to full medical clearance from offseason procedures. Some, like Sammy Watkins and Boobie Dixon, have been participating on a limited basis in the OTA practices, while others, like Leodis McKelvin and Aaron Williams have been held out of all activity.

Will some of the more notable names coming back from rehab be given the opportunity to participate more in the mandatory minicamp?

5. Name makers

Players a little further down the depth chart have all been working hard to prove themselves to the coaching staff and show that they deserve legitimate consideration for a spot on what is a very deep and talented roster.

Thus far players like TE Clay Burton, TE Marqueis Gray, S Jonathan Meeks and RB Karlos Williams have been among the younger players who have turned some heads. Can they carry that play in OTAs into minicamp and use it as a springboard into padded practices at training camp?