"For us to do something, give up a pretty good young player or players, it would have to be someone who we all felt would be a big difference maker," the manager said.
Leyland said that player could be a hitter or pitcher.
With the July 31 non-waiver deadline a week away, Leyland said Tigers general manager Dave Dombrowski always solicits his input about any players Detroit might be interested in or any possible deals.
Leyland said he told Dombrowski that he didn't favor making a deal that would make Detroit "only a little bit better."
"But that's not my area of expertise. I manage. I don't make deals," Leyland added.
Detroit's game Friday night against the Toronto Blue Jays was postponed due to rain and will be made up Sunday as part of a day-night doubleheader. The opener is scheduled for 1:05 p.m., with the makeup game at 6:05 p.m.
Shaun Marcum had been slated to start Friday night for Toronto against Detroit right-hander Rick Porcello. Both pitchers were pushed back to Saturday night, though more rain is expected.
Marcum (8-4, 3.36 ERA) was removed from his start Sunday at Baltimore after five innings because of a blister on his finger.
Brett Cecil will start the first game Sunday for the Blue Jays against Jeremy Bonderman. Jesse Litsch goes in the nightcap against Tigers right-hander Armando Galarraga.
Detroit (50-44) began Friday in a second-place tie with Minnesota in the AL Central, two games behind the Chicago White Sox. The Tigers have won two straight following a seven-game losing streak.
Not surprisingly, Leyland said the key to Detroit's postseason chances lies in the middle of the diamond.
"If we get consistent starting pitching, we have a shot," he said. "If not, we don't."
It began raining just as the Tigers were completing batting practice Friday a little after 5 p.m. The Blue Jays did not take batting practice on the field.
"It happens sometimes," Toronto manager Cito Gaston said. "I've seen it many days."