ATLANTA --- For years, TBS billed the Atlanta Braves as America's Team. No more.

Now TBS wants to be America's Network.

After several years of cutting back its ties to the Braves, TBS begins a seven-year contract of national weekly telecasts with Boston's game at Toronto on Sunday.

Chip Caray and Buck Martinez will be paired as announcers for the game; Caray also will work with Ron Darling during the network's 26 weeks of Sunday afternoon games.

TBS had exclusive coverage of the four division series and the NLCS last season. TBS will televise the division series and the ALCS this season.

The playoffs are the most attractive prize, but the full season of weekly national games also are important as TBS tries to shed its image as a one-team network, a label earned through three decades with the Braves.

"We want to be recognized as a national entity very quickly, and we think we can do that," Martinez said Wednesday, when he was at Turner Field to join Caray for a practice telecast.

Still, 30 years with the Braves won't be easily cast aside. Just as some viewers may still turn to TBS expecting to see the Braves, they may have to be convinced over time the network can be the place they turn for a national perspective.

"It's always an uphill fight when you're doing something new and you want to establish yourself, but we think we've put together a team of people who have been around the game who can elevate the game to one of national significance," Martinez said.

TBS producer Glenn Diamond says having the division series and NLCS last year was an important first step in establishing a new perception for the network.

"From the standpoint of us being a national entity, I think us having the playoffs last year as a starting point really helped," Diamond said. "Everybody had to go to TBS and they know TBS has done the postseason and the Braves weren't in it. We did all four division series and the NLCS, so that was our coming out party to the national audience."

Turner Sports spokesman Jeff Pomeroy said the 2007 playoffs provided instant proof of the importance of the national baseball package to TBS.

"The playoffs last year produced the highest ratings in the network's history for any programming," Pomeroy said.

"Baseball fans came to us for the playoffs last year. For national fans looking for regular-season games, they have to know to stop at TBS now every Sunday. That's our big challenge with this package."