Major League Baseball has put rock ‘n’ roll in its starting lineup, and musical acts are being invited to step up and improve their averages.

MLB for years has run a Web site that is fan-friendly and successful at selling tickets as baseball teams play around the country. Music acts are borrowing that Web design, since it has solved many of the problems that touring musical acts face.

So far, the business of artist Web sites is relatively small; the job is mostly handled by their labels. Signatures — the largest licensing and merchandising company in the music world, with 2005 revenue of more than $130 million — is banking on an increasing number of artists taking control of their own Web presence.

Signatures has worked with MLB Advanced Media (aka MLB.comMajor League teams) to create a joint venture to operate Web sites for major rock acts beginning this summer with Tom Petty, Ringo Starr, George Michael, Lindsay Lohan and Rob Thomas, all of whom are touring during that time.

The idea is that all traffic regarding the artist — marketing, ticketing, Webcasting, fan clubs, mobile content and merchandising — are driven from a single site.

“MLB has created a successful Web site business with tools that work for music,” says Signatures Networks CEO Dell Furano. “They have invested in the technology and infrastructure. And with our marketing knowledge and their marketing knowledge, we have a perfect partnership.”

Signatures handles the licensing and merchandising of 125 major music acts, mostly at concerts, which are the company’s bread and butter.

In addition, the company runs Web sites for 20 of the acts, including U2, Madonna and Kiss; it first worked with MLB.com last year on baseball-concert promotions with Bon Jovi and Jimmy Buffett.

“In the music world, whether they want to admit it or not, most successful artists are outstanding entrepreneurs,” says MLB.com chief exec Bob Bowman. “For them, the Internet is the ideal tool. For us, we have to make it economically smart and cool. And in the digital world, when you serve the fan, you have served the musician.”

MLB.com, which also runs the Major League Soccer site, has created a template for the 30 teams in the league that involves everything from radio to chat rooms. Furano says the challenge for Signatures is convincing artists they need a consistently changing, entertaining Web site to get fans to make regular return visits.

“Sites are highly personal, and we spend a lot of time taking artists through Web sites that work and ones that don’t,” Furano notes. “It takes content editors who are journalists, which MLB.com has. This is a huge business that has been created, and we think it can become a bigger business.”

But the baseball-rocker connection goes deeper than just sharing similar formats. For one thing, MLB and Signatures are also developing a site with Def Leppard that will involve a cross-promotion with Major League Baseball.

In addition, MLB is ramping up the league’s presence at major rock festivals to score a few runs with a younger, hipper crowd.

Major League Baseball Properties’ “Access to the Show,” a traveling exhibit in a trailer that is parked at major music festivals, is embarking on its biggest trek yet in its four-year history. The MLB Road Show started traveling with the Virgin College Mega Tour featuring Yellowcard on April 7, and continues through May 6. It gets parked at CMA and Bonnaroo in Tennessee in early June and then travels with the Vans Warped tour to 46 cities between June 15 and Aug. 13.

“Festivals give us enough time to interact with the fans,” notes Steve Armus, Major League Baseball’s VP of licensing. “We’re parked there eight to 12 hours a day. At other shows, they were bypassing us.”

As part of the Vans Warped Tour, the MLB Authentic Collection will sponsor the Vagrant Records stage, bringing together music and baseball in new ways. The sponsorship gives Major League Baseball Properties access to the Vagrant bands for participation in its activities, from interacting with fans at the MLB Road Show batting cages to judging the New Era Cap design contest, and a nationwide sweepstakes at Champs Sports stores.

“We realize that baseball gets a stodgy reputation,” Armus says. “But when we see kids with dreadlocks or hippie types at Bonnaroo or the guys covered with tattoos and piercings at Warped in the batting cages, we’re a lot cooler than we ever thought.”