The Phoenix Mercury will become the first WNBA team to wear a corporate sponsor’s logo prominently on its jerseys this season. In a deal being announced today, identity-theft protection company LifeLock Inc., will sponsor the team for three years in a deal said to be worth at least $1 million a year.

The Arizona-based company, which also sponsors NASCAR, will be the team’s presenting sponsor and get its name on the team’s warm-up jerseys and its arena. It is also to offer complimentary membership to WNBA season ticket holders.

The WNBA did a deal prior to last season with McDonald’s in which the fast food giant sponsored Tip-Off for the league’s 12th season. Players wore the Golden Arches on a Tip-Off logo on their jerseys during the home openers, but the logos weren’t as prominently displayed as LifeLock’s will be on Mercury jerseys.

The Mercury will still wear its team logo, but Mercury will be a much smaller badge-style logo on the upper left – similar to the way the L.A. Galaxy’s logo appears on the MLS team’s jerseys since Herbalife began sponsoring that team in 2007.

So, while we’re used to seeing corporate logos on jerseys overseas, they are beginning to seep into U.S. sports more frequently than they have in the past. The Boston Red Sox and Oakland A’s wore sponsor logos on their jerseys and helmets during the two games that opened the 2008 MLB season in Japan. The Puerto Rican team wore Best Buy logos on their jerseys during the 2009 World Baseball Classic.

Since we used to seeing logos just about everywhere these days, does this bother you? Do you think the uniforms for NFL, NBA, MLB and NHL teams are still sacred?

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