Alex Smith never saw the hit coming. He knew the protection around him had broken down, and he saw defenders converging upon him. Then he felt it.

A tug from behind, then a crushing weight from above.

Milliseconds unfolded in slow motion.

“I’ve got a human being on my back,” Smith realized, “in the middle of a football game.”

A 284-pound human. Aaron Donald of the Los Angeles Rams — the most dominant defensive lineman in the NFL — had jumped on Smith’s back to bring him to the ground. 

A football game. Smith’s first in 693 days. This was his first hit since the tackle that shattered the bones in his right leg, which doctors at one point worried they would have to amputate.

The leg. Smith, with Donald still on his back, realized the same leg that endured 17 surgeries and hundreds of hours of rehab, bore the bulk of the body weight of two people. After collapsing and then getting back up, he realized the leg felt good. It was fine. He was fine. 

He had done it. Pressed into duty on a dreary October Sunday after an injury to Kyle Allen, the Washington Football Team’s starter, Smith pulled off the most improbable and courageous comebacks that football has seen. 

Three weeks later, the 36-year-old Smith received another confirmation he had come full circle. 

WEEK 11 PICKS:Can Smith lead Washington to a win vs. Bengals?

Facing the New York Giants, Smith again relieved an injured Allen. While attempting to direct a fourth-quarter comeback, Smith threw an interception with 1:23 left, ending the game.

When he returned home to his wife, Elizabeth, and three children, the first questions directed at him had nothing to do with his health. 

“It was like, ‘What were you doing at the end of that game? Who were you throwing to?’” Smith told USA TODAY Sports with a laugh. “The household energy, it has progressed for them too. It’s no longer just happy for me to be out there, it’s ‘What were you doing?’”

The following week, Smith started Washington’s game against the Detroit Lions just three days shy of the two-year anniversary of his injury. He remains the team’s starter for the foreseeable future.

The NFL might as well ship Smith the Comeback Player of the Year hardware right now.

Smith acknowledges he has exceeded his own expectations. He didn’t initially cook up this dramatic comeback mission. This is just where his recovery journey and mental fortitude brought him. 

He has reached this point thanks largely to the disciplined approach that has guided him through every valley and peak of his career. Now he aims to restore Washington to winning and to inspire people to shatter limitations by living in the moment.

“I didn’t know this was going to happen,” Smith said. “I tried to remain as optimistic as possible throughout it, but certainly there were times when doubt creeps in and you get frustrated. But I think the key was not being afraid to put it out there and attempt it. This was a progression.

“As daunting things can seem at times, for me, keeping it short-sighted — one goal at a time, one step at a time — allowed me to get the ball rolling and make progress. There was no way I ever thought about playing again in the NFL or certainly starting a game again in the NFL when I was sitting in a wheelchair.”

At that time, Smith simply wanted to save his leg. After the completion of his surgeries, he needed additional highly specialized treatment plans​ and went to the Center for the Intrepid, which neighbors the San Antonio Military Medical Center at Fort Sam Houston and serves military patients and veterans with severe extremity injuries, amputations and burns.

“I went there feeling sorry for myself,” Smith said. 

The medical team at the Center for the Intrepid, working in conjunction with Smith’s northern Virginia-based team, saved Smith’s leg, and the relationships he built with fellow patients, most of them service members injured in combat, helped him recalibrate. There, Smith rekindled the resolve that carried him through the tumultuous first eight years of his professional career to orchestrate three Pro Bowl campaigns between 2013-17.

During those early years in San Francisco, Smith found himself plagued by anxiety and burdened by the expectations of saving the franchise that made him the No. 1 pick of the 2005 NFL draft.

He adopted the mantra “just live,” which helped him block out distractions, numb himself to pressure and focus on living in the present. 

“I think the biggest thing is certainly trying to make the most of every day. Not let your mind wander,” Smith said. “Our minds can wander, and we all have that internal voice, and sometimes it can get the best of us, and for me, I try to snap back and be present.”

He didn’t concern himself with how to lead the 49ers to a Super Bowl. Instead, he approached each day with the goal of doing what he needed to improve in that 24-hour window. He prepared for each game as if that contest alone mattered. In Smith’s mind, because that was the one day or game standing in front of him, only those deserved his attention and energies.

“He has an unbelievable ability to have a singular focus and unbelievable desire and work ethic to accomplish goals,” Brian Johnson, Smith’s former Utah teammate and one of the quarterback’s closest friends, told USA TODAY Sports. “He obviously has a fantastic support system with Liz and the kids and his family as well. But he has such a unique mental makeup that challenges have never been an issue for him. He’s always found a way to rise above the occasion. This comeback was no different.”

While recovering from surgery and confined to a hospital bed or wheelchair, Smith focused on keeping his mind sharp and his motivation strong. 

“I certainly had dreams and things like that, but it was all about a progression, and it was all about taking that first step and then moving to the second and I’m so thankful that things have kept progressing,” Smith said. “There was a long time where it was just about walking, and then it was just about playing with my kids, because those things are more important. But I was so fortunate that things kept progressing. And I wasn’t going to stop.”

As the 2019 NFL season drew to a close, Smith told Johnson he felt so good that he intended to seriously pursue playing in 2020. Johnson wasn’t surprised.

“It kind of naturally happened, after last season when he said he was feeling good, doing some footwork stuff, drops and drills,” said Johnson, the offensive coordinator at Florida. “He could obviously still throw the ball, but it was a matter of getting to where he felt comfortable starting and stopping.”

Smith went from inactive during the first four weeks of the season to the backup in Week 5 after coach Ron Rivera benched Dwayne Haskins and elevated Allen. But with Allen’s stint as starter lasting just three games prior to his injury, Smith ascended further and now has a chance to solidify his spot as Washington’s long-term answer at quarterback.

But none of that consumes his thoughts. He has displayed obvious rust at times and then gone on hot streaks. His next goal is regaining consistency and producing victories.

“Living week to week in the NFL is the name of the game,” Smith said. “Finding a way to go out there and play winning football at the quarterback position and put us in position to win a game is what I’m doing. … I’m enjoying this opportunity so much, I’m not even looking past Sunday. That’s it. Doing everything I can to play well. There will be time to reflect when the season’s done and see what’s what.”

Smith does have another off-field goal: to inspire others to exceed limitations and “just live.”

He believes his story and on-field success will help him accomplish this because he drew inspiration from the comebacks of players like Dallas Cowboys linebacker Jaylon Smith and members of the military who returned to service.

The quarterback recently designed a clothing line bearing his “just live” mantra and is partnering with the apparel company Attitude Is Free. All of the proceeds from the clothing sales will go to the Center for the Intrepid, Smith said. 

Through his return to football, Smith has learned an invaluable lesson he believes will carry him throughout his life. 

“I had over a year of doubt about what I could do, and the rest of life,” Smith said. “As crazy as this sounds, coming back and playing tackle football at the NFL level, I really do feel this: the rest of my life will be better for me having done this, and knowing that I don’t have any limitations. … Whatever comes at me next, and that I can take that head on.”

Smith only hopes that when people look at him, they’ll realize the same also applies to their lives.

Follow USA TODAY Sports’ Mike Jones on Twitter @ByMikeJones and listen to the Football Jones podcast on iTunes.