No surprise, a large number of teams are expressing interest in San Diego Padres closer Heath Bell and the club’s other relievers.

The New York Yankees are among the suitors, major league sources say.

The Padres are not yet exchanging offers with other clubs, but that could change by the end of their current 10-game trip, which began with two losses in three games at Seattle.

At the All-Star break — after the Padres visit the San Francisco Giants for four games and the Los Angeles Dodgers for three — the discussions regarding Bell and others are likely to intensify.

The Texas Rangers, Philadelphia Phillies, Milwaukee Brewers and St. Louis Cardinals are among the other teams that have contacted the Padres about their bullpen pieces, sources say.

The Yankees, knowing that the trade market is thin in quality starting pitching, likely will pursue relievers aggressively after suffering numerous injuries in their bullpen.

Right-hander Joba Chamberlain (elbow surgery) is out for the season. Right-hander Rafael Soriano (elbow) could return after the All-Star break, but the team is not counting on contributions from lefties Pedro Feliciano (rotator cuff) and Damaso Marte (shoulder).

The Yankees need another lefty besides Boone Logan to counter the Red Sox, against whom they are 1-8 this season. Most of the Padres’ top relievers — Bell, Mike Adams, Luke Gregerson, Chad Qualls and Ernesto Frieri — are right-handed. But Adams is quite effective against left-handed hitters, limiting them to a .468 OPS this season.

The problem for the Yankees and other interested clubs is that the Padres will move Adams only if they receive an extraordinary offer, sources say.

Adams, who turns 33 on July 29, is earning a relatively modest $2,535,000, and the Padres control him through next season. He would become the team’s closer if the Padres trade Bell, a potential free agent. A year from now, if the Pads are out of contention, Adams could be their most attractive trade chip.

— Ken Rosenthal and Jon Paul Morosi