By Don Muret, Staff Writer, SportsBusiness JournalThe Twins announced this morning they have reached an agreement in principle on a 25-year naming-rights deal with Target Corp. for their new ballpark, set to open in 2010. Financial terms were not disclosed. The deal could be worth $4-6M annually based on the team's market size, said Premier Partnership's Randy Bernstein, who helped the A's complete a 30-year, $120M deal for Cisco Field in '06. The A's have yet to build their park. The average annual value for naming rights at MLB ballparks is $2.6M, according to SBJ research. For Target, the ultimate value to put its name on the Twins ballpark depends on its full sponsorship package, Bernstein said. The basic elements have been agreed on, but a final contract has yet to be signed and it is still too early to determine the scope of Target's brand activation at the $412M facility, Target Dir of Communications Lissa Reitz said. In addition to Target Field, the Twin Cities-based retailer also gets naming rights to Target Plaza, a pedestrian bridge and public gathering space connecting the ballpark to downtown Minneapolis. There is a plan for Target to sell Target Field-branded merchandise at the ballpark, which would have no effect on Delaware North Sportservice's stadium retail exclusive, confirmed Twins President Dave St. Peter. Those new items will be available at Sportservice stands. "The question is if Target is going to do any on-site sales and if the deal is tied to any type of licensed products," Bernstein said. "The dollar value really jumps when it's tied to extended business and other platforms."