Venture capitalist Joe Lacob joined the former group this week, when he and partner Peter Gruber completed their $450 million purchase of the Golden State Warriors. Lacob previously had been a minority shareholder in the Boston Celtics, but wasn’t involved much in decision-making. Plus, he lived on the wrong coast (now he just lives on the wrong side of a bridge).

Lacob made his money as a partner with Kleiner Perkins Caufield & Byers, the Silicon Valley firm he first joined in 1987. Some of his earlier deals included AutoTrader and Sportsline, and he later refocused on the energy sector (yes, including the infamous Terralliance deal).

But the Warriors deal seems to mark an end of Lacob’s active venture capital days.

A Kleiner Perkins investor says that Lacob is not listed as a managing partner on new funds currently being raised, and that he is not expected to do new deals going forward (although he will continue to manage existing portfolio companies). 

And then there was the following comment from SF Chronicle scribe Scott Olster:  

“This is no dilettante. Lacob, in order to run the Warriors, is putting aside his work as a venture capitalist, whose company has been backing ideas to benefit the environment. Instead of saving the planet, Lacob will now try to save the Warriors, and I think we can all agree he has chosen the path more vital to mankind.”

In other words, it looks like Lacob is following the path of Celtics majority owner Wyc Grousbeck — who left his VC gig at Highland Capital Partners in order to manage the Celts fulltime. This stands in contrast to fellow Celts majority owner Steve Pagliuca, who still spends his days working at Bain Capital (well, when he’s not running for U.S. Senate).

Neither Lacob nor a Kleiner Perkins spokeswoman returned requests for comment.