Rubenstein stressed that Steinbrenner "means business," saying that the owner "wants this message to be heard loud and clear."
The statement comes one day before a meeting of Yankees executives in Tampa, Fla. Steinbrenner will gather his top lieutenants from both the New York and Tampa offices to discuss the state of the team.
One of the primary topics figures to be player personnel, as the trade deadline is five weeks away. General manager Brian Cashman will be in Tampa for the meeting, as will team president Randy Levine.
Despite Steinbrenner's view that the players may be lacking the desire to win, both manager Joe Torre and captain Derek Jeter squashed that notion before Monday's game against the Orioles.
"Wanting to win and winning are two different things. Everybody knows how badly he wants to win," Jeter said. "As long as the intensity is there. For a while, we weren't playing with intensity. That was a concern for everybody."
"I hope [Steinbrenner] wouldn't be happy," Torre said. "We'd be concerned if he was happy at this point in time. These players aren't happy. ... The only thing I defend is that just because we don't win, that doesn't mean we don't want to. It's not as easy as it sometimes looks."
After rallying for a 6-4 win over the Orioles on Monday, the Yankees (39-37) are 5 1/2 games behind the first-place Red Sox and 3 games behind the Twins in the Wild Card race.
"The man is passionate. He needs to win; He spends money to win," Torre said. "When we don't win, he's not happy. A lot of times, when we win, he's not happy, because he wants to win more."
Matsui's back: Hideki Matsui was back in the outfield on Monday night, his first game in the field since spraining his right ankle on June 12 in St. Louis.
"I think I can play defense," Matsui said through his translator when asked how close to 100 percent his ankle is. "I don't know a percentage, but I think I can play the way I usually play if I wasn't injured."
Matsui, who had started 31 games in left, 25 in center and four in right this season, was penciled into the left-field spot by Torre, who said he didn't want Matsui to have to cover the extra ground in center in his first game back.
Permanent arrangement? Matsui's start in left may be a sign of things to come, as Torre started Tony Womack in center for the second consecutive game.
Womack and Bernie Williams will likely share time in center, leaving Matsui to tend to his familiar territory in left.
"To me, it really doesn't matter where I play in the outfield," Matsui said. "In terms of just being used to being in left field, perhaps it would be beneficial."
Womack had played just 18 games in center field in his career before Sunday, his last start at the position coming in 1999. Torre plans to play Womack and Williams in center for the foreseeable future, hoping that the platoon can help keep Williams fresh.
"I want it to be a trial, more than day to day," the manager said. "I'd rather give Matsui a smaller field to deal with, and I'd rather keep him in one place. We'll try to work center field between Bernie and Tony."
Rest for Sheff: With Matsui vacating the designated hitter spot for the first time in 13 games, Torre inserted Gary Sheffield in the lineup as the DH, giving him a day off from right field.
Ruben Sierra got the start in right, his first of the year after getting six starts in left.
"It's more mental than anything. To get up, have the same intensity for 162 games, then the playoffs and World Series, it takes a lot out of you," Sheffield said. "I pride myself on bringing the same intensity every day, so any time you can get a breather, it rejuvenates you, mentally."
Sheffield, who was ejected from Sunday night's game for throwing his batting helmet to the ground after being called out at first base, said he expects to hear from Major League Baseball about the incident.
Sheffield doesn't believe he'll be suspended, but a fine is likely.
On deck: The Yankees and Orioles meet in the second of three games at Camden Yards on Tuesday, as Chien-Ming Wang takes on Sidney Ponson.