The Spurs lost the 1995 WCF in the last minute of Game 1. It was a close game, but Robinson split a pair of FT at around the 1 minute mark, the Spurs got a stop -- a steal, actually -- and Sean Elliott got fouled on the break and missed both of his FT. Instead of being up 3 or 4, which they should have been, the Spurs were up 1.
I think Rodman basically decided he was done after Elliott's missed FT. He appeared to be the guy who was supposed to be guarding Horry (who spent most of that play hanging out above the 3 point arc and then took a dribble and two steps inside the arc to hit his game-winner -- un-Horry like, in retrospect); Horry, however, was all alone for most of that play. Rodman made a relatively half-hearted effort to drop down and get a steal after the initial play set up and then hung out in the middle for the rest of the play. It made some sense, given that Hakeem threatened the middle as the clock wound down, but when Hakeem found Horry all alone, Rodman was standing almost on the baseline and his man was above the arc and above the free throw line. Someone else should have rotated, but nobody did. Horry hit the shot, the Rockets stole Game 1, Rodman was mentally done, and the series was basically over.
It wasn't all Rodman's fault, but it would be ridiculous to say that he was blameless.