For Chris Johnson, this season -- scratch that -- his entire NBA career has been all about him making the most of his opportunities to play.

Depending on the severity of Avery Bradley's Achilles injury, Johnson may very well find himself playing an even more prominent role for the Celtics to close out this season.

Bradley was unable to play in the second half of Boston's 94-80 loss to Chicago on Monday because of what he described as tendinitis in his Achilles.

"It just comes from not playing for a long period and coming back full speed," said Bradley, who earlier this season had a stretch in which he missed 19 out of 22 games due to a right ankle sprain.

Bradley added that the Achilles had been bothering him prior to Monday's game, "but I've been playing through it, just getting treatment. (Monday night) it got the best of me."

By no means does Johnson wish ill upon any of his teammates, but he knows that Bradley's status may very well create another opportunity - there's that word again - for him to continue establishing himself not only with the Celtics but also as an NBA player.

After back-to-back 10-day contracts with Boston, the Celtics signed him to a four-year, $3.27 million contract although each of the last three years are non-guaranteed.

So Johnson knows there's no time to relax and get comfortable with his status.