When Steve Mariucci took over as the 49ers' next head coach ahead of the 1997 season, Steve Young already was established as a star quarterback in the NFL. 

By that point, Young had 12 years in the league under his belt. He had two MVP trophies to his name and multiple Super Bowl rings. When Mariucci arrived for training camp in '97, though, Young still found a way to surprise his new coach

"When we came into training camp, most teams will test their athletes to see if they're in shape and high schools and colleges will do the same thing ... Steve Young would really be the best guy as far as our test was concerned," Mariucci said Monday on 95.7 The Game's "Damon, Ratto & Kolsky" show. "He was right up there and would pass most of the time all the receivers and running backs and corners.

"This guy was a great athlete. Forget about being 36, 37 and 38 years old, he was really a top-shelf, well-trained athlete."

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Young was turning 36 in just three months during Mariucci's first training camp with the 49ers. It was well established that he was one of the best dual-threat QBs ever, a player well ahead of his time.

 

Before Mariucci arrived on the scene, Young had accumulated over 25,000 passing yards and more than 3,500 rushing yards. He already had 124 passing touchdowns and 34 rushing TDs. And then Young led the NFL in completion percentage (67.7) for the fourth straight year in his first season under Mariucci. Young had 3,029 passing yards, 199 rushing yards and 22 total TDs in '97.

Young was again great in '98 with 4,170 passing yards, 36 touchdowns through the air, 454 rushing yards and six more TDs on the ground. But he played just three games in '99, ending his career with a bevy of concussions.

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"It's a shame, I really do believe I had him in his prime," Mariucci said. "Had he not gotten a couple of concussions, I think he could have played into his 40s just like we saw Brett Favre and Tom Brady and Drew Brees. Steve Young was still throwing the ball very, very well late in his 30s."

While it's no secret Young is one of the greatest athletes football fans have ever seen, even a Hall of Famer can surprise his coach here and there with his ridiculous talent.