Donovan Mitchell is proving the Cavaliers’ window is now or never

Cleveland Cavaliers v Miami Heat | Megan Briggs/GettyImagesThe pressure is mounting for the Cleveland Cavaliers this season, and Donovan Mitchell has been carrying a team that came into the year with some very high expectations. His third-in-the-league 9.2 points per game in the fourth quarter is all the evidence anyone needs that the Cavs are going to go as far as he takes them this season, and frankly, it's now or never.

Cleveland is coming off a 60-win season that should have propelled them into the tier of true contenders, but it's not played out that way so far. A 13-10 start is hardly a disaster, yet it reflects how uneven the roster has looked around its best player.

Mitchell has been…