It must be that time of year again; adrenaline is high, workplace productivity is low, Cinderella is donning her glass slipper, and the faint aroma of hardwood in the air as the opening weekend of the NCAA tournament is upon us. By the time the dust settles on Sunday night, dreams will have been shattered, brackets will have been busted, and many a buffalo wing will have been delightfully devoured.

No one can debate that the thrill of watching your bracket come together perfectly is one of those feeling you cherish for a lifetime (or at least for three weeks in March). When it comes to the science of bracketology, however, there is some debate as to the favorite online destination for prognostication among NCAA basketball enthusiasts this year.

According to Hitwise, it was pretty much a three horse race this year in terms of the most popular online sports sites to fill out brackets. After all was said and done, ESPN.com’s Men’s Tournament Challenge beat out the competition with a 32.8% total market share of visits. Coming in a close second was Yahoo Sports Tournament Pick’em with 30.4% share, barely edging out CBS Sportstline’s Fantasy Mayhem at 30% share.

Rounding out the field, Fox’s College Bracket Challenge finished dead last with a 6.9% market share.

On average, users spent 15 minutes on any particular site when filling out their tournament brackets, which no doubt pleased advertising partners looking to market to what mostly constitutes a very young demographic.

Hitwise also reports that the share of searches for the term “ncaa brackets” were up 38% when compared to the same week’s statistics last year.