NEW YORK - Hank Aaron and Willie Mays are going to bat for a credit card provider, offering another "priceless'' experience in a commercial that makes its debut during Tuesday night's All-Star game.

George Brett, who will join Aaron and Mays in the Hall of Fame this summer, and San Francisco's Barry Bonds - who wasn't selected for the All-Star game - also appear in the new commercial for MasterCard International.

The Fox telecast from Boston's Fenway Park is expected to be one of the highest-rated TV shows this summer. All-Star ratings were up 13 percent last year after sinking to a low in 1997.

Even with the rise last year, the rating was 28 percent below what it was for the All-Star game in 1994, which came a month before a strike that ended the season prematurely and forced the first cancellation of the World Series since 1904.

Baseball has been struggling to rebuild its fan base since then and make itself a more attractive partner for marketers.

In addition to MasterCard, advertisers on this year's All-Star game telecast include the Blockbuster video store chain, brewers Anheuser-Busch and Coors, automakers General Motors and Nissan, Quaker State motor oil, discount broker Charles Schwab and John Hancock financial services.

Allstate Insurance, the nation's second biggest provider of property and casualty insurance, is launching a new advertising campaign with four commercials planned for the telecast.

The ads feature Allstate agents, claims adjustors and investigators who recount their own experiences on the job to demonstrate their personal commitment to the company's customers.

The new ads retain the longtime theme "You're in good hands with Allstate'' but each ad ends with the featured employee adding, "Mine.''

Raleigh Floyd, spokesman for Northbrook, Ill.-based Allstate, said the telecast was chosen for the campaign kickoff because it draws "a pretty attractive audience'' both in terms of raw numbers and the type of people who buy home and auto insurance.

The new MasterCard ad will be the fourth with a baseball theme in the "priceless'' campaign from the agency McCann-Erickson.

The card provider from Purchase, N.Y., showed a father taking his 11-year-old son to a ballgame for the "priceless'' chance for real conversation in the first ad in the series in October 1997.

Last year, it was the "priceless'' experience of taking a Little League team to its first big league game. Also last year, another MasterCard ad suggested that witnessing a record-breaking home run by Mark McGwire or Sammy Sosa was "priceless.''

The new commercial opens with a mother using a camcorder to show her husband and two children leaving for a game. "Camcorder: $400,'' the ad says. The ad shows Dad and the kids inside the car as they drive to the stadium and later as they head to their seats. "Three-hour tape: $7,'' the ad says. "Extra battery: $25.''

Aaron and Mays are in street clothes sitting with the kids. "Home movies with Hank Aaron and Willie Mays: priceless,'' the ad says.