Reggie Miller, the 42-year-old former Pacer who has been approached by the Celtics [team stats] to return from his two-year retirement, is putting himself through a tough workout routine to determine whether he can still withstand the NBA grind.

Miller told ESPN?s Dan Patrick yesterday that he still hasn?t made up his mind.
?I have no idea what I?m going to do,? he said on Patrick?s ESPN radio show. ?I?m working out twice a day. It would be irresponsible of me not to go full bore now to see what I can do. I?ll make a decision soon.

?Six or seven days ago I started two-a-days, and I probably have 10 days left of that,? he said. ?By the middle of September I should have an answer.?

Miller said he was ?shocked? when Danny Ainge initially called his former agent, Arn Tellem, in an attempt to lure the shooting guard out of retirement.