SALT LAKE CITY -- Decked out head-to-toe in green Boston Celtics apparel and a camera slung around his neck, Jordan Mickey looked like some sort of NBA tourist while standing inside the visitor's locker room at Vivint Smart Home Arena on Friday night. In a way, he kinda was.

Mickey's marching orders after the All-Star break were to make his way to Delaware and join the Maine Red Claws of the NBA Development League on their three-game road trip. After a month rehabbing a high ankle sprain, Mickey was set to engage in his first 5-on-5 action since the injury occurred while on assignment on Jan. 16.

But then Kelly Olynyk got shelved for a month due to a shoulder separation, David Lee got bought out and the Celtics stayed idle at Thursday's trade deadline. An itinerary change buzzed on Mickey's phone with updated instructions: Get to Salt Lake City immediately to join the Celtics.

The 21-year-old Mickey, the 33rd pick in June's draft, arrived in Utah late Thursday afternoon while the Celtics were wrapping up an off-day practice. The team still put him through an individual on-court workout and he was still getting up shots while most of his teammates headed for the bus. Celtics coach Brad Stevens said that Mickey wasn't likely to play Friday because he still had to shake some rust following the ankle injury. But when Boston's regulars underperformed in a lopsided loss to the Jazz, Mickey got tossed in for the final two minutes, 43 seconds.

If one message has been consistent to Mickey since his arrival, it was this: Stay ready for your opportunity. And despite the travel audible and his lack of on-court activity the past month, Mickey was ready for that late-game cameo.

Against the Jazz, Mickey finished an alley-oop lob from fellow rookie Terry Rozier and blocked a couple shots, including a Gordon Hayward layup attempt while scrambling from the weak side with help (he later added a more emphatic baseline swat of Jeff Withey). After the game, Stevens made sure to heap praise on the group of young players -- Mickey, Rozier, James Young, and R.J. Hunter -- for the way they played at the finish, because there's no such thing as garbage time for them.

"I'm happy to be able to just get an opportunity," said Mickey. "It’s all about taking your opportunity and showing what you can do."

With Boston's depth thinned, rookie Jordan Mickey could be in line to see playing time. Noah K. Murray/USA Today Sports

Mickey's reward for his efforts? That camera around his neck belonged to teammate Young, who also tasked Mickey with carrying the second-year guard's shoes to the team bus.

"All the [rookie] duties, you know?" Mickey deadpanned.

Yes, as Mickey's week hammers home, the life of a rookie is rarely glamorous. Despite creating a buzz for himself with his play in the D-League, Mickey's injury forced him to miss the D-League All-Star game in Toronto earlier this month, which might have been another chance to showcase his abilities. Stevens had said even before the injury that he was eager to get a look at Mickey, but Boston's logjammed frontcourt didn't offer much opportunity at the NBA level.

That might be changing now. With Boston's depth thinned, Mickey could be in line for minutes when a teammate finds foul trouble or is underperforming. The Celtics still have enough depth to cover Olynyk's absence -- at least at the moment -- but Mickey has shuffled a little closer to potential NBA playing time.

And Celtics fans are anxious to see what he can do in longer stretches. In 21 appearances with the Red Claws, the springy Mickey, an undersized power forward, is averaging 17.1 points, 10.4 rebounds and a league-leading 4.6 blocks per game. According to Basketball Reference, Mickey ranks second in the D-League in defensive rating (98.4) and ninth in Player Efficiency Rating (22.1).

Of course, his PER is far more eye-catching at the NBA level, albeit in a minuscule sample size. In nine minutes of floor time, Mickey owns a PER of 63.1. For sake of comparison, the league average PER is 15 and Steph Curry is the league-leader among qualifying players at 32.21 (or roughly half of Mickey's number).

The small sample size leads to some exaggerated numbers for Mickey -- like an offensive rating of 131 when he's on the court (albeit, offset by a defensive rating of 133.5). Even still, Mickey has grabbed 25 percent of all available offensive rebounds during his court time and owns a true shooting percentage of 84.6.

And, backup quarterback syndrome or not, four NBA appearances have left Celtics fans clamoring for more Mickey. Any reference to Mickey on social media is likely to fill your timeline with train emojis -- a playful reference to the "hype train" that Mickey rides on because of his intriguing talents.

Mickey still has a long way to go to becoming an NBA rotation player, but Olynyk's absence might tell us more about exactly where he stands at the moment. But he's rapidly earning Stevens' trust.

"If the situation presents itself, I’m not afraid to use him," said Stevens. "That’s for sure."

And Mickey's teammates are intrigued as well.

"Hopefully he’s ready for the opportunity if his opportunity does come," said All-Star point guard Isaiah Thomas. "I know he works tremendously hard and, when he does practice with us, he plays very well. He’s going to be a good player in this league. Like I said, I think he’ll be ready for his chance when his name is called."

Mickey acknowledged that there's no guarantee his number will get called again on Sunday. But he's proven he'll be ready if it is.

"You gotta be patient. That’s what I’m doing," said Mickey. "Just waiting my opportunity. [Friday] happened to be one; just have to wait for the next one. I know I’m a young guy, I gotta wait my time like everybody else had to do. That’s what everybody says: You just have to wait for your time, and that’s what I’m doing."

Beyond a basic curiosity to see what Mickey can do, here's another reason to get a longer glimpse of him if you're the Celtics: Boston will enter the summer with both Tyler Zeller and Jared Sullinger as restricted free agents, while Jonas Jerebko and Amir Johnson have player options. Making decisions on those players and their future in Boston is easier if you know exactly what you have in Mickey and whether he might be able to fill their shoes with a larger role in the future.