The best that's got away...

[DavorCroatiaFan]

Celtics have a long history of great players who come to Beantown to finish career and won (Phillip, Risen, Lovellette, Naulls, Howell, Embry, Archibald, Walton, Cassell, PJ) or try to won (Maravich, Bing, Gilmore, Wilkins, Marbury, Finley) or who  will won (Shaq, Jermaine) the championchips.
But there are players who's career blossomes after they left us...These 5 comes to mind:
PAUL WESTPHAL - traded to Charlie Scott, have 5 great years in Phoenix, 3-time all-nba first team, one time all-nba second team, injuries cut career short
CHAUNCEY BILLUPS - part of big Kenny Anderson trade, 5 times all-star, finals MVP, 2-time all-nba second team, great clutch player and leader of Pistons and Nuggets. One of big Pitino mistakes
JOE JOHNSON - part of Rogers/Delk trade. 4 time all-star, one third team all-nba selection...we could get Kedrick Brown in that trade...it stinks
BRUCE BOWEN - was practicly rookie with Celtics, later goes to Spurs, won 3 titles and have 8 all-defensive team selection (5+3)
NICK GALIS - 95% US fans would say WHO??
Galis was Celtics draft pick in 1979. Should be our rookie alongside Bird but broke arm in rookie camp and wouldn't offered a contract. Goes to Greec (his parents were Greek imigrans) and become one of the greatest european player of all-time.
-in 1983. in a match between Greece and North Carolina scored 50 points! The man who guard him? Michael Jordan!
-in 1987. led Greeks to European championchips, was brilliant in semis vs povwerfull Yugoslavia (37points) and even better in finals vs USSR (40 points).
-in 1989. in semis destroyed Marculionis and USSR with 45 points
Great, great scorer (11 time top scorer in Greek league, 8 times in Euroleague).
-Won 8 Greek league championchips and 7 cups
-according to "Wikipedia" Red Auerbach once sad that the biggest mistake he ever made was not keeping Galis.
I remember Galis, he was 6-1 shooting guard like Iverson, but unlike Iverson he was so strong. He was former boxer, got tremendus, Havlicek-like stamina, guick release...
Alongside Drazen Petrovic, Arvidas Sabonis and Oscar Schmidt the BIG FOUR of International players. Man, matching Galis with such a passer as Bird were would be phenomenal...
Peace

[Celtics4ever]

Pitino had a lot of blunders.   Anyone who started Potapenko did not know NAB basketball.  Catching is a prerequisite of say, scoring and rebounding.

Billups and Johnson still hurt.

[Andy Jick]

We had Ben Wallace in our grasp, but if I recall correctly, Rick Pitino wanted to make him a 2-guard?  Yikes!!!

Probably the one draft I remember being a devastating blow (looking back in hindsight) was in '89 when we drafted Mike Smith and could have drafted Tim Hardaway.  But then again, we got lucky with late picks like Reggie Lewis ('87) and Brian Shaw ('88) and picked up Dino Radja in the 2nd round of '89.

So you win some and you lose some...

[Roy H.]

Rick Fox and Brian Shaw were two Celtics who went on to win championships (with the hated Lakers of all teams).

[35Lewis]

We had Ben Wallace in our grasp, but if I recall correctly, Rick Pitino wanted to make him a 2-guard?  Yikes!!!

Probably the one draft I remember being a devastating blow (looking back in hindsight) was in '89 when we drafted Mike Smith and could have drafted Tim Hardaway.  But then again, we got lucky with late picks like Reggie Lewis ('87) and Brian Shaw ('88) and picked up Dino Radja in the 2nd round of '89.

So you win some and you lose some...

Actually Pitino wanted Wallace to play the 3 but Wallace went around telling everyone that we were trying to get him to play the 2 because he felt the only people that should ever shoot jump shots were guards.  Pitino may be wrong about what Wallace ultimately could offer but imagine if Wallace listened and developed a jump shot.

That 89 draft we also missed out on Kemp though that doesn't sting as much as it did back in the early 90's.

I would also like to add David Wesley to the mix even though he is nowhere near "The Best" to get away.

[cons]

anyone drafted after eric montross was picked 9th by us in 1994 - total bust. the list is not hugely devastating but includes eddie jones, jalen rose, aaron mckie

[Roy H.]

anyone drafted after eric montross was picked 9th by us in 1994 - total bust. the list is not hugely devastating but includes eddie jones, jalen rose, aaron mckie

The good thing about Montross, I guess, was that we traded him + the rights to Samaki Walker for Antoine + a 1st rounder (Ron Mercer).  That one worked out pretty well for us.

[celticsclay]

Out of curiosity does anyone think that Jr Bremer could have been a decent second or third string point guard in the nba? Not exactly, losing sleep over it, but last I heard he had been pretty successful over in Europe and was probably making the same or more as he would have made in NBA. So it might not be a clear case of a guy not being good enough for the league. Also, how often to you guys think players fall into this category? They could be backups or end of roster guys in NBA but opt for more prominant role and equal or better pay in europe (especially a few years back when Euro was doing better versus dollar)

[celticsclay]

By the way before anyone says I am crazy here is an article talking about fringe NBA players in europe making more money, but losing money in the long run cause of a worse pension system. A pretty interesting article in my humble opinion, and yes bremer is mentioned.
http://www.nytimes.com/2009/12/13/sports/basketball/13pension.html?_r=1

[kofanis0880]

Len Bias should go on this list regardless...

[cons]

anyone drafted after eric montross was picked 9th by us in 1994 - total bust. the list is not hugely devastating but includes eddie jones, jalen rose, aaron mckie

The good thing about Montross, I guess, was that we traded him + the rights to Samaki Walker for Antoine + a 1st rounder (Ron Mercer).  That one worked out pretty well for us.

good point, i forgot about that. i think that was ml carr who made that move, was it? would definitely be his finest moment, and better than any move pitino made after him.
this was definitely pre-mark cuban too, i think. god, what was dallas thinking? 

[xmuscularghandix]

Good call on the Nick Galis. Very few people are aware of what we had slip through our fingers.

[slamtheking]

hadn't heard of Galis until now but if he was as good as advertised, C's could have had a better chance at getting another title in Bird's first 4 years.  Put a scorer like Galis alongside Tiny, Max, Bird and Cowens/Chief instead of Chris Ford -- that would have been a high-scoring starting line-up. 

In terms of the losses, Bowen doesn't hurt so much.  didn't show a lot when here.  Billups was a good trade at the time.  They got Kenny Anderson who provided the vet leadership and PG skills the team needed with a young Toine, Mercer and later PP. Using JJ instead of Brown was a real bonehead move.  Anyone watching those 2 that season could see JJ had more skills. 
I'd actually put Rick Fox ahead of Bowen.  Fox played well when he was here--very good defender but not so great on offense.  went to LA not by choice but because C's wouldn't keep him.  found his niche there.  not sure why he gets boo'ed at the Garden when he comes back.  he certainly doesn't deserve it.

[Brendan]

Clearly Billups was a bad trade Kenny was over the hill when we got him and Billups went on to have a very good All Star level career as the perfect complimentary PG. Pitino should have traded Toine and Mercer.

[Celtics4ever]

Pitino was a horrible NBA coach.  Look at some of the studs he let get away like Joe Johnson and Billups. 

As for Len Bias he might have been better than Jordan.

http://www.youtube.com/watch?v=1DGVlXxG2Pk&feature=related

http://www.youtube.com/watch?v=y4u4MdSGSDo&feature=related