INDIANAPOLIS -- The highlights still play in the minds of those waiting and dreaming and itching at the Colts training facility. They're the moments that taught them that Anthony Richardson had more to offer than they ever really knew.

There he is, dropping back against the Rams with All-Pro menace Aaron Donald crashing into his face from the left edge, standing tall to see above the outstretched arms and flicking a bomb down the right sideline that hit Alec Pierce in stride for a 38-yard gain through pass interference.

There he is in that same game, dropping back with clean feet and delivering a seed across the middle for 30 yards, patiently enough to allow Josh Downs to turn around and wait for it at its catch point and with enough velocity to where neither the high or low safety had time to lay a hit.

And there he is, in that same game, running play-action and being flushed to his right, only to fire a side-arm throw to hit Mo Alie-Cox in stride to let his tight end rumble for a 35-yard touchdown.

The moments are few and far between, thanks to the training wheels of a rookie ramp-up and an AC joint sprain that ended that rookie season after just 84 pass attempts. But in a league where scouts believe that if a player does something once, he can do it again, the Colts and Richardson saw something they haven't forgotten.

"I’m going to tell you one of the things that really surprised me with Anthony because I was concerned about it: This guy is a passer," general manager Chris Ballard said. "Here’s this big, talented athlete. I mean, this guy is a legitimate passer, and I believe that. I think he’s going to continue to get better and improve the more he plays. But Anthony can play from the pocket and throw the ball accurately."

He was hoping before. He's seen it now.

The data was limited to 84 pass attempts, but it didn't contain the red flags about Richardson's passing the way his college numbers did. He threw a catchable pass on 85.7% of attempts, per Sports Info Solutions, which aligns with 49ers quarterback Brock Purdy's numbers for the full season. Only Texans quarterback C.J. Stroud fared better than his 1.2% interception rate.

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The moments came whizzing by so fast to the man who hurled them. By his fourth and fifth career starts, Richardson wasn't ready to gush over his highlights, not in a loss to the Rams or in the aftermath of those separated shoulder, which had him in a dark place for weeks.

But part of his rehab has been getting his mind and spirit back to the place that fired those slingshots. In watching back his film, Richardson realized what surprised him the most about his rookie season.

"On the field, I can just say the way I play," Richardson said. "I kind of expected that from myself, but I kind of shocked myself a little bit when I was doing the things I was doing. It just made me happy and let me know that I was working, and my hard work was paying off."

Last spring, Richardson soared up draft boards due to the most athletic profile for a quarterback the NFL Scouting Combine had ever seen at 6-foot-4 and 244 pounds with a 4.43-second 40-yard dash time, a 40.5-inch vertical jump and a 129-inch broad jump.

The appeal of his arm was in its sheer power. But in that ferociousness came the questions about its accuracy and consistency, which resulted in a 53.8% career completion percentage and 17 passing touchdowns in his one starting season at Florida.

It created a scouting journey unlike any other for the Colts. Though Ballard fell in love with the talent, discipline and personality of Richardson, he admitted even on the glow of draft night that concerns about his accuracy were "fair." Assistant general manager Ed Dodds had to be won over to a prospect with so few starts and completions in his career, and he eventually asked Richardson about his mechanics to explore how fixable they were.

As director of college scouting Morocco Brown kept pounding the table for the quarterback he watched on a daily basis during practices at Florida, new coach Shane Steichen had to convince owner Jim Irsay that he could develop Richardson as a passer.

"The forward pass is the way you're going to get it done," Irsay said at the time. "This isn't the Olympics. It's not running and jumping. Those things are great, but in the end you have to be an outstanding quarterback with a feel for the game, with vision, who can assimilate things very quickly." Shane really did see him in his mind, see what he needs to see to feel he can develop into an outstanding passer."

The Colts eventually reached unison in wanting Richardson, though not quite enough to trade up to secure him in the draft.

They were elated to land him at No. 4 and began to script the offseason program around getting him the reps to learn the muscle memory, footwork and offensive understanding to throw with timing and ball placement. His early practices were up and down in these areas. So when they named Richardson the starter after his preseason debut, they built a game-plan that could accentuate this growth in manageable ways, even if it meant limiting the overall upside. That evaluation time was cut short by the brain injury that knocked him out for the second half of his second start and for his third start.

But falling down 23-0 in the first half of his return against the Rams became a blessing in disguise. They unleashed Richardson with a pass-first focus, hoping to generate the chunk plays and explosive gains to pile up scores in little time. And then it was working, as Richardson completed just 11 of 25 passes but averaged 8.0 yards per attempt to lead the Colts to a 23-23 tie headed into overtime, before Matthew Stafford drove the Rams down for a game-winning score.

"I just keep thinking about Los Angeles, with Donald coming down the pike, and he stood tall enough to deliver that ball," running back Jonathan Taylor said after the season ended. "It was insane to see the accuracy that the ball was throw with. The velocity."

"I was like, 'That's special. That's special.'"

Six days later, Taylor signed a three-year, $42 million deal to return to the Colts.

Richardson followed it up with the same efficiency against the Titans the next week, completing nine of 12 passes for 8.2 yards per attempt. Then he sprained his throwing shoulder on a designed run, and his season was over.

But the Colts saw what they wanted to see most out of Richardson this year, even in just 84 attempts. A finished product was never going to come. But a capable one has.

They've gone from hoping he can be a passer to believing it.

That's why getting and staying healthy has become all the more paramount. The Colts and Richardson don't want to talk about small sample sizes and flashes forever. When he does get consistent playing time, defenses will have a chance to counter game plan, making it a necessity to keep making advancements in his game.

"Let’s not go crown him," Ballard said. "Let’s not stamp him yet."

Richardson plans on throwing again next month. The hope is to keep him throwing.

There's more in that healing shoulder than they knew before.

"Whenever that day does come," Richardson said, "I’ll be trying to light it up.”

Contact Nate Atkins at natkins@indystar.com. Follow him on Twitter @NateAtkins_.

This article originally appeared on Indianapolis Star: Colts: How Anthony Richardson surprised with his passes