ABC News January 23, 2015

Deflate-gate: NFL Players Pile on New England Patriots Quarterback Tom Brady

WATCH: NFL Breaks Silence on Deflate-gate

Many NFL players, both current and former, say they're having a hard time believing Tom Brady's denial that he knew anything about the alleged use of deflated footballs during the team's AFC Championship win last Sunday over the Indianapolis Colts.

Brady told reporters Thursday that his preference for pressure was 12.5 pounds per square inch. Footballs, which are weighed before the game, must be inflated to no less than that.

"I have no knowledge of anything," Brady, a three-time Super Bowl winner, said. "I was as surprised as anybody when I heard Monday morning that this happened."

Deflate-Gate: Patriots Players Tested to See If They Can Tell Whether Balls Are Under-Inflated Deflate-Gate: Tom Brady Says He 'Didn't Alter the Ball in Any Way'

The Patriots said they are cooperating with the NFL's investigation.

Here is a look at what Brady's biggest critics are saying:

1. Jesse Palmer, former New York Giants quarterback

Elsa/Getty Images
Sports commentator Jesse Palmer is shown prior to start of Super Bowl XLVIII at MetLife Stadium between the Denver Broncos and the Seattle Seahawks on Feb. 2, 2014, in East Rutherford, N.J.

The ESPN analyst and former star of ABC's "The Bachelor" told "Good Morning America" today he's in disbelief that Brady didn't notice the ball was deflated below 12.5 pounds per square inch.

"I wouldn't believe that. Quarterbacks, again, they're so particular about the footballs they throw in these football games. It's kind of like your Starbucks order. Some quarterbacks like footballs that are worn in. Some like them inflated. Some like them deflated," he said.

2. Richard Sherman, Seattle Seahawks cornerback

Elaine Thompson/AP Photo
Seattle Seahawks' Richard Sherman runs in NFL football practice, on Jan. 21, 2015, in Renton, Wash.

“I think people sometimes get a skewed view of Tom Brady,” Sherman said Wednesday at a news conference in Seattle. “That he’s just a clean-cut [guy], does everything right, never says a bad word to anyone and we know him to be otherwise.”

Sherman's history with Brady goes back to the Seahawks' 24-23 victory over the Patriots on Oct. 14, 2012.

As Sherman tells the story, Brady told him to “see him after the game when they win.” After the Seahawks won, Sherman was taped asking Brady, “You mad bro?”

Though Brady had no response, the video went viral.

3. Mark Brunell, former Green Bay Packers quarterback

Sam Greenwood/Getty Images
Former Jacksonville Jaguars quarterback Mark Brunell, left, speaks with Jacksonville Jaguars owner Shahid Khan prior to being inducted into the Pride of the Jaguars at EverBank Field on Dec. 15, 2013, in Jacksonville, Fla.

"I did not believe what Tom had to say," former Packers, New York Jets and Jacksonville Jaguars player Brunell said on ESPN. "Those balls were deflated. Somebody had to do it. I don't believe there's an equipment manager in the NFL that would, on his own initiative, deflate a ball without the starting QB's approval ... That football is our livelihood. If you don't feel good about throwing that ball? Your success on the football field can suffer from that."

4. Jerome Bettis, former Los Angeles/St. Louis Rams and Pittsburgh Steelers halfback

George Gojkovich/Getty Images
Former running back Jerome Bettis of the Pittsburgh Steelers looks on from the sideline before a game against the Cleveland Browns at Heinz Field on Sept. 7, 2014, in Pittsburgh, Pa.

"I'm so disappointed because I thought this was a perfect opportunity for Tom Brady to go and say 'You know what? I made a mistake. I blew it. It's on me. I'll take the blame here, and this will go away.' He didn't do that," Bettis, nicknamed "The Bus," told ESPN. "I'm disappointed in you, Tom Brady."

5. Brian Dawkins, former Philadelphia Eagles and Denver Broncos safety

Michael Perez/AP Photo
Former Philadelphia Eagles' Brian Dawkins is seen before an NFL football wild-card playoff game between the Philadelphia Eagles and the New Orleans Saints, on Jan. 4, 2014, in Philadelphia.

"This is unbelievable," Dawkins, nicknamed "Weapon X," said on ESPN. "For you not to know what you touch every play? ... The equipment manager is being thrown under the bus now. Now he's the guy. Now he's the one responsible. He took it upon himself to doctor up the balls when nobody else knew about it? That hard [to believe]."

6. John Madden, former Oakland Raiders coach

David Dermer/Diamond Images/Getty Images
Former NFL coach John Madden waves to the crowd after being introduced before the 2012 Pro Football Hall of Fame Enshrinement ceremony on August 4, 2012, at Fawcett Stadium in Canton, Ohio.

"That would have to be driven by the quarterback," Madden told The Sports Xchange on Wednesday. "That's something that wouldn't be driven by a coach or just the equipment guy. Nobody, not even the head coach, would do anything to a football unilaterally, such as adjust the amount of pressure in a ball, without the quarterback not knowing. It would have to be the quarterback's idea."

7. Troy Aikman, former Dallas Cowboys quarterback

Maddie Meyer/Getty Images
Troy Aikman, former NFL player and current NFL analyst answers questions from the press at Super Bowl XLVIII Media Center on Jan. 28, 2014, in New York City.

"It's obvious that Tom Brady had something to do with this," Aikman told Dallas sports radio station KTCK-AM on Thursday. "For the balls to be deflated, that doesn't happen unless the quarterback wants that to happen, I can assure you of that."

8. Hines Ward, former Pittsburgh Steelers wide receiver

Joe Sargent/Getty Images
Announcer Hines Ward looks on before the game between the Pittsburgh Steelers and the Baltimore Ravens on Nov. 18, 2012, at Heinz Field in Pittsburgh, Pa.

"It's cheating," Hines Ward said on Wednesday. "Regardless of how you may want to spin it. It helps Tom Brady, provides a better grip on the football, especially in bad weather conditions like rain."

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