Sometimes it’s the smallest things that reveal an athlete’s greatness, and when it comes to Tom Brady’s career with the New England Patriots, it doesn’t get much smaller than this: Cody Kessler following him around the team’s facility in Foxborough, close as a shadow, carrying a notepad, scribbling down everything Brady said or did.

Kessler had been with the Eagles during training camp last year before struggling in a couple of preseason games, suffering a concussion, getting cut, and signing with the Patriots. Over three seasons with the Cleveland Browns and Jacksonville Jaguars, he had thrown eight touchdowns and five interceptions and won two of the 12 games he started. Rank all the quarterbacks in the NFL on their resumes and achievements, write their names in order based on that criteria, and Brady and Kessler might be the poles on that list. No wonder Kessler tracked him like a puppy dog, eager and hopeful to collect whatever scraps of wisdom Brady happened to shed.

“He’s the best player ever at that position, and that’s who we should want to be,” Kessler said just days before the Patriots beat the Eagles, 17-10, at Lincoln Financial Field on Nov. 17. “It’s just little stuff that I pick up here and there — small stuff, small stuff. Without being too specific, just his process, the way he does things, the way he talks to guys on the field if they don’t connect on a throw, the way he talks if they do connect on a throw, how he feels about it, how he talks about it, the way he watches film, picking his brain. It’s been awesome. Obviously, there’s no one better to sit behind and learn from. I want to stay here as long as I can and continue to learn from him.”

Brady and the Patriots beat the Eagles, 17-10, last November at Lincoln Financial Field.
YONG KIM / Staff Photographer
Brady and the Patriots beat the Eagles, 17-10, last November at Lincoln Financial Field.

It might seem ironic at first that, as of Brady’s announcement Tuesday morning that his “football journey will take place elsewhere” and his reported decision to sign with the Tampa Bay Buccaneers, Kessler has, in a way, outlasted Brady in New England. Kessler is still a Patriots quarterback. After 20 years, six Super Bowl victories, nine Super Bowl appearances, 11 regular-season and Super Bowl most-valuable-player awards, Brady is not.

Those accolades and Brady’s story and celebrity — the rise from sixth-round pick to all-time great; the supermodel wife; the new-age diet that kept him playing excellent football into his 40s — have caught most people’s eyes and held their attention over the years. But anyone who had listened to the most credible and knowledgeable reporters and analysts around Brady and the Patriots understood that this situation isn’t ironic. It was inevitable. Brady was going to leave New England and become a free agent because there were no worlds left for him and Bill Belichick to conquer together. The challenge for him will be to try to replicate those accomplishments — specifically, another championship — without Belichick. The challenge will be to transfer those small-but-vital habits, the daily work and routines that led to the spectacular Sundays, to a different setting.

“Examples of Tom’s greatness are limitless,” Belichick said in a statement. “We witnessed how he prepared when he wasn’t playing, how he performed when he got his opportunity, what he did to continuously improve, his leadership, his mindset, the example he set, and, of course, the person he is. I’m extremely grateful for what he did for our team and for me personally.”

So was Kessler. So was a journeyman quarterback who happened to fall into a job backing up the best of all time. Brady didn’t have to pay him any mind. Brady had nothing invested in Kessler’s growth and improvement. And yet …

“He’s been the best teammate I’ve been around — the way he is, the way he does things,” Kessler said. “He takes time, helping me out if I have a question here or there. He’ll ask me stuff. He keeps you in the game. He wants to win, and he brings everyone else along with him, and I think that’s the key to a leader: a guy who can be that dominant on the field but still get guys to play their best. That’s something he does day in and day out.”

Former Eagles quarterback Cody Kessler backed up Brady last season with the Patriots.
JOSE F. MORENO / Staff Photographer
Former Eagles quarterback Cody Kessler backed up Brady last season with the Patriots.

That he treated Kessler like an equal doesn’t mean that Brady is St. Francis of Assisi. It means that he has always minded the tiny details when it came to himself and his team, because those oft-unseen actions and provisions — such as making sure your backup is as prepared as he can possibly be — are often the difference between success and failure.

There was no better example of Brady’s thinking and approach in this regard than the immediate aftermath of Super Bowl LII, of Brandon Graham’s strip-sack that sealed the Eagles’ 41-33 victory. In the bowels of U.S. Bank Stadium, eye black still streaked above his cheeks, Brady credited the Eagles for their performance: They played a great game. They’re a great team. We never played on our terms. But after seven minutes of the same kinds of questions, after throwing for three touchdowns and a Super Bowl-record 505 yards and still losing, Brady finally broke.

“They made a good play,” he said. “They made a good play at the right time. They made one good play at the right time.”

He shrugged his shoulders and forced a smile that said, What else do you want me to say? His answers might have sounded dismissive of the Eagles: They made one play on defense all night. Good for them. It was more likely the opposite. That single play … the moment that Brady held the ball an extra tick and Graham reached out with his left hand … meant everything. And Tom Brady knew it. The smallest things. Someone should write that down.