Aaron Donald was thought to be under-sized.

That doesn’t matter anymore.

In 2014, Donald was trying to prove his NFL worthiness as a defensive tackle from Pittsburgh at the Senior Bowl.

Donald got in his stance in South end zone at Ladd-Peebles Stadium in Mobile, Ala. and preceded to shred all interior linemen who tried to block him. After training in metro Atlanta under the guidance of former Falcons defensive lineman Chuck Smith, Donald was doing all he could to impress then Falcons defensive line coach Bryan Cox.

Smith was on the outer perimeter of the drills yelling instructions.

“Rip,” Smith yelled. “Speed to Power.”

Fast forward, Donald remembers those days fondly. The Rams’ five-time Pro Bowler and one-time NFL Defensive Player of the Year, has certainly made a place for himself. Now, he is preparing to face the Patriots in Super Bowl LIII at 6:30 p.m. on Sunday at Mercedes-Benz Stadium.

“For sure, I’ve came a long way,” Donald told The Atlanta Journal-Constitution. “There is always going to be people that are going to second guess you and doubt you. But all you can do is go out there and play ball. Let your game speak for you. I’ve came a long way. Put a lot of work in. To be here now, it’s a blessing.”

At 6-foot-1 and 280 pounds, Donald was thought, by some scouts, to be too small to play along the interior defense line in the NFL. But his superior quickness has allowed him to thrive.

After the buzz at the Senior Bowl, Donald’s stock rose. The Rams selected him 13th overall in the 2014 draft.

The Falcons picked Jake Matthews with the sixth pick in 2014 and took a flyer on defensive tackle Ra’Shede Hageman, who was also at the Senior Bowl, with the 37th overall pick in the second round.

Donald and Hageman were the stars working under Cox in Mobile.

“For sure, me and coach Cox stayed in contact for the first three or four years in the league,” Donald said. “Then we lost contact because of numbers switching. But you know, he was a good guy. A real good guy.”

Donald has been named to five straight Pro Bowls and four consecutive All-Pro teams. He led the league with 20.5 sacks last season and was named the Professional Football Writers of America’s defensive player of the year. He was the second Rams player to receive the award, joining former defensive end Robert Quinn (2013) since it was first awarded in 1992. He became the first defensive tackle to win the award since the Buccaneers’ Warren Sapp (1999).

Donald has been a force for the Rams this season. He started all 16 games and has 59 total tackles (41 solo). His 20.5 sacks were a franchise-record for an NFL-record minus-183.5 yards.

Donald led the NFL in both tackles for loss (25) and quarterback hits (41) to go along with four forced fumbles. He had seven multi-sack games during the 2018 regular season.

In two playoff games, Donald has no sacks, four tackles and three tackles for loss.

“Aaron has been unbelievable,” Rams coach Sean McVay said. “I think when you really look at it, the stats can be misleading with regard to the production and the influence that a defensive player is having on the game.”

He was consistently double-teamed against the Saints in the NFC Championship game and that wasn’t enough to keep him from hitting the quarterback three times.

“I feel the sliding and double teams,” Donald said. “You’re going to feel it. That’s what is going to happen.”

With so much attention on Donald, defensive tackles Ndamukong Suh and Michael Brockers have had more one-on-one matchups.

“If you focus on one guy, the other guys are going to get their one-on-one (matchups) and win,” Donald said. “As long as somebody is winning, I’m happy.”

Donald doesn’t care how the Patriots try to block him.

“This is what I dream about,” Donald said. “This is what I’ve worked for. This is what you train for to play in big games like this and have an opportunity to play in the world championship.”

Donald will be counted on to help slow down New England’s rushing attack.

"Well, you look at the two teams we've played, who were great – well, I say great – but, they were great running teams, that neither one of them made (more than) 50 yards rushing,” Rams defensive coordinator Wade Phillips said. “Suh, Donald and Brockers are, really, responsible for that. Playing more of the running game when they needed to rather than rushing the passer every play and they were able to do that well."

The Patriots have put up a fortress around quarterback Tom Brady in the playoffs. He hasn’t been sacked while completing 64 of 90 passes in wins over the Chargers and Chiefs.

“They have a great quarterback back there that knows how to get the ball out of his hands,” Donald said. “They play good together up front. They have been running the ball very strong in the playoffs. We have our hands full. But we have a bunch of great guys.”