MIAMI — Listen to Dwyane Wade, Chris Bosh and Erik Spoelstra rave about sophomore combo guard Tyler Johnson, and you get the feeling the Heat might really believe in the upstart 23-year-old.

Then look at the front office's actions, and you know for sure. 

Beloved point guard Mario Chalmers' dismissal last month can be directly traced to Johnson's ascension. Heat president of basketball operations Pat Riley indicated as much after trading the veteran point guard to the Memphis Grizzlies in a four-player swap earlier this season.

"It has a lot to do with the young [players]," Riley said at the time. "We've decided to give these young guys some room to grow and gain confidence, and they're not just going to do it in the D-League." 

Riley mentioned Johnson and rookies Justise Winslow and Josh Richardson by name, but Winslow was logging major minutes before the deal and Richardson still hasn't secured a rotation spot.

The Heat had to free up as much playing time as possible for Johnson. His eye-opening start left them with no other choice. 

As Miami Heat's Coach Spoelstra can attest, there's no shortage of reasons for believing in the bouncy 23-year-old.

"You don't have to put him in a box of, 'What position is he?' He can play on the ball, he can play off the ball; that's why he's a winning player," Spoelstra said.

The hoops world is either still sleeping on Johnson's something-from-nothing story or just waking up to it.

Johnson is the latest proof that it's possible to go from undrafted training-camp invite to NBA D-Leaguer to big league rotation regular in a little more than a year. He's just 51 games into his NBA career, and the first 32 came with the injury-riddled Heat squad that limped to a 37-45 finish last season—their worst mark since 2007-08.

But those closest to the situation have seen enough to recognize real potential. 

"It's one of those situations where people are like, 'Who is this guy?' We know who he is," Bosh said. "You better bring your lunch pail, because you're going to have to work [against him]."

Johnson is already the best three-point threat in their regular rotation (45.7 percent) and the most consistent finisher among their perimeter players (52.5 field-goal percentage). A shooting guard at Fresno State, he's still finding his form as a playmaker (the left-handed guard admitted "I couldn't throw a right-handed pass to save my life last year"), but he's still dished out 3.0 assists per 36 minutes.

As the Miami Herald's Ethan Skolnick noted before a recent shoulder strain sidelined Johnson, his offensive output had been as reliable as any in the Heat's rotation:

His defensive intensity has taken him from benchwarming afterthought to averaging 22.8 minutes per game since the season's third game.

"[Defense is] a non-negotiable with Spo," Johnson said.

Johnson hounds opponents like a parasite clinging to its life source. On the whole, he's knocked 2.8 percentage points off his matchup's regular field-goal conversion rate (from 43.0 to 40.1). More impressively, he's made his biggest impact on the game's most efficient shots—opponents have lost 10.8 percentage points on both threes and shots within six feet against him.

"Anything that he does now doesn't really surprise me," Bosh said. "He's knocking down shots, he's getting guys involved and he's playing great defense."

On the rare nights his shot isn't falling, he can find buckets off the bounce. When his scoring isn't there, he can power the offense by dishing. He's always a disruptive defender no matter what's happening at the opposite end, and he regularly punishes teams who don't respect his presence on the offensive glass (4.5 offensive rebound percentage, second among all guards who have logged 100-plus minutes).

Johnson has embraced his role as Miami's backcourt chameleon.

He's been both a sprinter alongside the speedy Goran Dragic and a half-court tactician when sharing the floor with Wade. To Johnson's credit, he's been effective regardless of the assignment. He ranks inside the 90th percentile as both a pick-and-roll ball-handler (1.08 points per possession, 94.7th percentile) and a spot-up sniper (1.23, 92.4).

"You can see a difference between this year and last year, and it's his confidence," Wade said. "He's always been athletic and able to finish, but now he is having the ball more and getting more comfortable."

And yet, Johnson continues fighting as if his roster spot is in jeopardy.

"Once you feel like you've made it is when it all starts to go away," he said. "The biggest thing is for me to keep my head down and continue to get better."

As inspirational as these first few chapters have been, it's the unwritten portion of Johnson's journey that invigorates this fanbase.

He won't celebrate his 24th birthday until May. He hasn't even approached a full season's worth of big-stage games. He's logged 30-plus minutes in only four games and finished with double-digit field-goal attempts seven times.

His overcrowded hype train might be itching to leave the station, but this is only the beginning of what's shaping up to be a long, productive career.

"I'm not here to just be an NBA player and make an NBA salary," Johnson said. "I'm here because I love the game of basketball, and I want to try and be the best I can be."

All quotes obtained firsthand. Unless otherwise noted, statistics used courtesy of Basketball-Reference.com and NBA.com.

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