Credit: MATEI/GVK/

Bling-a-ding ding!

L.A. Laker Sasha Vujacic made a slam dunk when he proposed to tennis champ Maria Sharapova last Tuesday.

A beaming Sharapova, 23, recently stepped out with her un-missable new engagement ring from her beau, 26.

"This ring makes a statement. It's no wonder why Maria is smiling in the photos! " jewelry expert Michael O'Connor tells

O'Connor gives Us more details on the Grand Slam winner's bling: the center stone appears to be a cushion-cut diamond of approximately 7 to 8 carats on a thick, split-shank platinum band. See more shots of Maria's ring.

Estimated cost, according to O'Connor: $250,000.

After nearly a year of dating -- they first stepped out together at a November 2009 U2 concert -- Vujacic proposed to Sharapova in his Manhattan Beach, Calif. home. No wedding date has been announced.

Back in August, the Slovenia-born basketball star says he and Sharapova has "helped each other" become better at their respective sports. "We both understand what the other is doing and going through, and what it takes to do well in what we do," he said of Russia-born Sharapova.