Clearly, stellar guard Rajon Rondo has turned the Celtics' "Big Three'' into the "Big Four,'' but on Saturday afternoon Mavericks coach Rick Carlisle surprised the media by suggesting that the three "Heatles'' should add backup point guard Mario Chalmers to the group. "I felt that he's been a big part of who they've become,'' Carlisle said after practice at the AmericanAirlines Arena. "He's a better all-around player than people probably believe. Off of this series, he's their fourth most dangerous player if you look at the stats. "He's a kid that's not afraid of the moment as everyone saw in the finals of the college championship game. … We have to treat him with a high level of respect and we are.'' Chalmers has made the fifth most 3-pointers in the playoffs and leads the Heat in 3-pointers made and percentage (30-of-77 for 39 percent), including 12-of-28 (43 percent) in the Finals. He's averaging 10.6 points this series, and has a 14-to-7 assist to turnover ratio to go with six steals. Many second-guessing Heat fans are wondering why coach Erik Spoelstra hasn't countered Carlisle's move of inserting lightning-quick 6-foot guard J.J. Barea into the starting lineup in Games 4 and 5 with Chalmers, who is considered a better defensive player than veteran guard Mike Bibby. Also, Bibby, 33, has clanged 17 of 66 (26 percent) 3's in the postseason. "No,'' Chalmers said when asked if he was starting Game 6. "I would love to be starter but at the same time, coming off the bench here I found my role and I found where I could impact the game.'' Even Barea, the X factor in Dallas' Game 5 win with 17 points, including 4-of-5 3-pointers and five assists, hinted that a long-armed Chalmers presents a tougher obstacle on his dribble-drives.