NEW YORK -- Yankees higherups aren't thrilled with the team's start, or surely their 15-13 record to date, and general manager Brian Cashman, one of the disappointed decisionmakers, suggested he believes the team is underachieving to this point.

"There's a lot of talent here,'' Cashman told CBSSports.com. "We have to work on getting it going on a consistent basis.''

Other Yankees people suggested they believe that other than ace CC Sabathia, iconic shortstop Derek Jeter, Curtis Granderson, Nick Swisher, the bullpen and maybe Ivan Nova, there's been a lot of underachievement going around.

The biggest stars who are the biggest culprits so far include Robinson Cano (.689 OPS), Mark Teixiera (.222 batting average) and Alex Rodriguez (.433 slugging percentage). The rotation has been another area of disappointment.

"I think out offense has been inconsistent. And out starting pitching, which was perceived as a strength, has been injured and inconsistent,'' Cashman said. "We are still finding ourselves.''

The rotation has recovered some after a dreadful beginning. "Our starters have been better the last three weeks,'' Cashman said, "but our offense has been worse. When one thing gets patched up, another springs a leak. But that's the nature of the beast.''

It's been a rough last week in yankeeland with the loss of Mariano Rivera, who has vowed to return after he tore the ACL and meniscus in his right knee in a freak shagging accident. Cashman expressed faith the team would band together under the circumstances

Asked if he expects the big stars to start hitting, Cashman shrugged. "I hope so,'' he said.