The defending champs are reeling, the No. 1 seeds are far from perfect and the potential for upsets never has seemed higher.

Is this really the NCAA women’s basketball tournament?

Yep, an event that has been dominated by a handful of powerful teams, and often plays out so close to form it’s almost boring, begins today with plenty of contenders but without a clear favorite.

“I see a number of teams that when you look at the bracket, you don’t see the sure wins,” Tennessee coach Pat Summitt said. “I think these are the toughest first- and second-round games I can ever remember.”

Take Summitt on her word. She has guided the Vols to the NCAA Tournament every year since it started in 1982 and has won six national championships.

Tennessee (26-3) begins this tournament as the No. 1 overall seed but is coming in off an overtime loss to Georgia in the semifinals of the Southeastern Conference tournament.

No. 6 seed TCU plays today at Temple. TCU coach Jeff Mittie was arrested Wednesday for suspicion of drunken driving in Newton. He was in Kansas to watch the NJCAA Tournament in Salina.

Two other No. 1 seeds, Penn State and Texas, lost in the championship games of their conference tournaments. Only Duke among the No. 1s comes in with a winning streak — 10 straight since losing to a Florida State team that did not make the NCAA Tournament.

Connecticut, winner of the last two national titles, began the season as the favorite after returning everyone from last year’s championship team. But the Huskies have lost two of their last four games and have four losses this season. In the previous four years combined, they had lost only five times.

Connecticut (25-4) plays Ivy League champion Penn in Bridgeport, Conn., one of 16 first-round games at eight sites Sunday. There are another 16 games at eight sites today.

This is the final run for an outstanding senior class that includes Connecticut’s Diana Taurasi as well as Alana Beard and Iciss Tillis of Duke, Nicole Powell of Stanford, Nicole Ohlde of Kansas State, Kelly Mazzante of Penn State, Chandi Jones of Houston and Shereka Wright of Purdue.

“In my experience with college basketball, this is the best (class) that I’ve ever seen,” said Stacey Dales-Schuman, a former Oklahoma standout.

“This senior class right now is frightening. A lot of WNBA players are going to lose their jobs.”