As much as it stung to watch LeBron James leave to join the Miami Heat, that gave opportunity for the Cleveland Cavaliers to invest in making a new star and things are beginning to pay off as Kyrie Irving is proving why he was worth the No.1 overall pick a few years back.

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Though James' high praise for the second-year point guard has rumors swirling the two could eventually join forces in Cleveland, both players simply are focused on the stellar competition each currently provides for the other.

James looks to improve to 8-1 against his former team while guiding the Miami Heat to an 11th consecutive victory as they host Irving and the Cavaliers on Sunday night.

The Cavaliers finished an Eastern Conference-worst 19-63 the season after James' departure while the Heat made it to the NBA finals, but winning the draft lottery allowed Cleveland to select Irving with the No. 1 overall pick.

While James has won another MVP and his only championship since joining Miami, Irving's potential has Cleveland fans believing in a bright future -- one that has the possibility of including both.

Irving, despite missing 11 games with a broken finger, has averaged 23.5 points, made his first All-Star appearance and won the 3-point contest at All-Star weekend after winning rookie of the year in 2011-12.

James, who can opt out of his current contract in 2014, has taken notice of Irving's talent, leading to rumors he would consider a return to his former team.

Whether James joins Irving is a possibility neither is focusing on at this point. For now, Irving simply realizes facing James always will provide a challenge.

"He's taken everything everybody said about him that he didn't do well (when he first left Cleveland) and is proving it all the time now," Irving said. "That's as simply put as you can say it. He's doing everything people said he couldn't do. It's fun to watch."