Seventeen years ago, he was such an unknown that it would have been unthinkable to refer to him as “QB2” for the University of Michigan. Three weeks ago, the man now known far and wide as QB12 led the Patriots to a fifth Super Bowl championship, earning his fourth game MVP award in the process.

This is Tom Brady.

From college nobody, to sixth-round draft pick deemed by many as a throwaway, to maybe the greatest quarterback to ever play the game.

“Brady cemented himself as the best quarterback in NFL history by not only winning his fifth Super Bowl but by willing it to happen, refusing to let a team that trailed 28-3 with less than three minutes left in the third quarter stop believing,” wrote David Haugh in the Chicago Tribune.

Over the next 18 game minutes in Super Bowl LI, the Patriots outscored the Atlanta Falcons 25-0, the last 19 of which came on two touchdowns punctuated with a pair of two-point conversions and a field goal, forcing the first overtime game in Super Bowl history.

The Patriots received the kickoff and Brady completed 5 of 6 passes for 50 yards in the extra period, with a 75-yard drive culminating in James White’s 2-yard touchdown run for a victory that marked the greatest comeback in the history of the NFL’s championship game.

“[Brady] was the same as he always is: cool, calm, and collected,” New England wide receiver Danny Amendola told The New York Times. “He’s the leader, the general, the best ever and that is the end of the story.”

And what a story. Brady was suspended for the first four games of the 2016-2017 season after being accused and punished for (maybe) deflating game footballs in a victory over the Indianapolis Colts in the 2015 AFC Championship Game.

“I’ve been labeled a cheater. I’ve been suspended. My mom is dealing with cancer. I’ve been ripped for my Donald Trump friendship. I’m playing the Super Bowl against the MVP of the league (Matt Ryan),” Brady said after the improbable win over the Falcons. “I was a sixth-round pick, No. 199. Nothing is easy. Nothing is handed to me.”

So how did the ugly duckling blossom into a swan after he entered the NFL as a relative nobody?

“People don’t understand. Tom walked through the door wanting to be known as the greatest quarterback who ever played when he is done,” wide receiver Deion Branch said after the Patriots defeated the Philadelphia Eagles 24-21 in Super Bowl XXXIX. “He is on a mission for that. Nothing is going to change that. Deep down, it’s his greatest fuel.”

It seems a strange goal considering Brady’s lowly draft status.

“He’s a good, tough, competitive, smart quarterback that is a good value,” coach Bill Belichick said after selecting Brady. “We’ll just put him out there with everybody else and let him compete and see what happens.”

What happened was quarterback Drew Bledsoe went down with an injury, Brady took over, and the rest is (unlikely) history.

He ranks fourth in career passing yards (61,582), fourth in career touchdowns (456), and third in career passer rating (97.2). In terms of the playoffs, Brady has played in more games (34), thrown for more yards (9,094), and completed more touchdowns (63), than any player in history.

He has also led New England to 13 division titles and holds the NFL record for most passes attempted without an interception (358).

Showing no signs of slowing down at age 39, Brady is making it increasingly difficult to argue against his status as the greatest of all time–or, as he is known across New England, “The G.O.A.T.”

His performance in Super Bowl LI merely cemented his status.

“This was greatness personified, the most accomplished quarterback to ever take a snap showing us why after a first half when he looked like nothing more than an over-the-hill guy pushing 40,” Haugh wrote. “This is how legends are made.”