Andrew Stevenson made his big league debut with the Washington Nationals on Sunday. His call-up came in a time of need — injuries and a bereavement leave had left the Nats short of outfielders — but the call-up wasn’t without merit. The 23-year-old former LSU Tiger had put himself back on the fast track after a slow start in Triple-A.

It was a dogged climb for the speedy 2015 second-round pick. Promoted to Syracuse on May 1 after hitting a heady .350 with Double-A Harrisburg, Stevenson found himself straddling the Mendoza Line six weeks later. Then he picked up the pace. From June 10 onward, he went 48 for 159 (.301), hitting safely in 30 of 40 games.

His modus operandi is slash and burn. Stevenson’s stroke is geared toward the gaps — he has just six home runs in 1,216 professional plate appearances — and he’s a running threat once he gets on. The native of Lafayette, Louisiana swiped 39 bags a year ago, and he was 9 for 10 in stolen base attempts after joining the Triple-A Chiefs.

His Double-A manager sees some raw power lurking in Stevenson’s lanky frame, but he largely concurs with the slash-and-burn label.

“He’s a definitely a contact hitter,” Matt LeCroy told me earlier this season. “He’s got good hand-eye coordination and an ability to put the barrel on the baseball. With his speed, if he puts the ball in play, he’s giving himself a chance to get on. I see him hitting in the leadoff spot, or maybe the two-hole.”

Not surprisingly, the up-and-coming table-setter views himself the same way.

“I’m just trying to get on, whether that’s by getting a base hit or by walking,” said Stevenson. “I’m not a guy who’s going to hit 40 home runs for you. That’s not my game. I just want to get hits. I want to put balls in the gap, and at the same time, I’ll take my singles and steal second.”

The lefty swinger hasn’t made many mechanical changes since inking a professional contract. He raised his hands slightly after coming out of college, but other than that, “it’s just been minor tweaks — nothing where I’d say, ‘I did this there, that there.’” His swing has remained “pretty much the same.”

Staying on an even keel has arguably been his biggest challenge. Each time he’s moved up a level, he’s allowed his heart rate to rise — and his chase rate to rise along with it. The self-aware youngster owned up to that fact when we spoke in the days leading up to his promotion to Triple-A.

“When you go up a level, you want to show people what you can do, and at first I’ve kind of forced things,” admitted Stevenson. “But it’s once you become more relaxed when you can show them what you can do. It’s when it becomes, ‘All right. I don’t have to do anything crazy, I just have to go up there and swing at good pitches.’ That’s the major key. If you’re chasing bad pitches, you’re going to get yourself out more often than they get you out.”

LeCroy saw that first hand last year. More recently he’s seen what can happen when Stevenson succeeds in slowing things down.

“He came up for seven or eight weeks at the end, and he was chasing a little bit,” said the Harrisburg skipper. “He was a big swinger, an aggressive swinger. This year he’s shortened his zone up a little bit. He’s laying off pitches, and he’s hitting balls to both gaps and down the lines. He’s a lot more locked in. He had a great spring training with the big-league team, and definitely opened up a lot of eyes. He still has work to do, but I think he’s got a pretty bright future.”