After three-plus seasons as head coach, the Pacers finally made the necessary move of firing Jim O’Brien on Sunday.

O’Brien was given a leash of sorts through his first three seasons as Larry Bird and David Morway constructed the team as part of a major rebuild, but their recent struggles forced them to go against previous comments regarding O’Brien’s job security.

Indiana won 36 games in his first two seasons and 32 in 09-10, putting them just outside the playoff picture in the Eastern Conference but never high enough in the lottery to land an impact player through the draft.

Thanks to the maturation of Roy Hibbert, the health of Mike Dunleavy and the addition of Darren Collision, the Pacers jumped out to a 10-9 record and notched statement wins against title contenders like the Heat and Lakers.

However, a loss on Dec. 8 to the Bucks started a steep decline that has seen the Pacers lose 18 of their last 25 games – including a trio of three-game skids and a six-game losing streak that ended against the Nets on Friday night.

Including the inability to close out games, the team’s struggles have coincided with the down play of Hibbert. He’s averaging just 8.3 points and 5.1 rebounds on 37.4% shooting in January and hasn’t posted a double-double since Jan. 7 when he had 10 points and 14 boards against the Spurs.

The center has looked great physically, but mentally he appeared to hit a wall after O’Brien criticized his play through the media. That certainly wasn’t the main reason for his firing, but more than halfway through his fourth season it’s safe to say that the Pacers were no longer listening to their coach.

Mike Wells of the Indianapolis Star reports that assistant Frank Vogel is expected to take over the position in the interim, but that Bird will have a say on who plays.

I’ve had a sense for a while that O’Brien’s rotation wasn’t exactly what Bird and Morway desired. He has shuffled big men in-and-out of the lineup, often playing someone like Josh McRoberts 30-plus minutes one night and placing him on the inactive list the next.

If anything, Vogel (through Bird’s urging) will keep a constant rotation and provide more consistent time for rookie Paul George. It will also be very interesting to see how Hibbert responds.

As improved as their defense has been this season, the Pacers have struggled mightily on offense. They are shooting 43.7% from the field, ahead of only the Bucks and Cavaliers.

Plain and simple, something needed to be done. O’Brien wasn’t the coach that was going to bring the Pacers out of their haze and it’s still possible that their lengthy playoff drought could end in April.

The Pacers entered Sunday’s action two games back of the Bobcats and 76ers for the final two playoff spots in the Eastern Conference.

They have a series of very winnable games coming up, so the transition from O’Brien will have to be a quick one.