If you are a glass half full type of person, to look at this in a good light you can think:
1) After playing a lot more minutes than past years and carrying a larger than usual share, it's good for Manu to get some rest before the playoffs.
2) If Barry comes back before the end of the regular season, this will allow him to get minutes.
3) It'll force Duncan and Parker to up their level of play before the playoffs.
Of course, this is assuming that the injury is relatively minor and shouldn't affect him after some rest.