Back in Spring Training, Pirates manager Derek Shelton couldn’t hide his enthusiasm after watching relief prospect Blake Cederlind pitch in live batting practice for the first time. With his blonde hair flowing in the Bradenton, Fla., breeze, the right-hander threw power sinker after power sinker on a back field at the Pirate City complex. “That,” Shelton said in February, “will make you smile.”

On Tuesday, Shelton delivered a few words that made Cederlind smile: “You're a big leaguer now, man.”

The Pirates activated Cederlind, the hard-throwing reliever, from the taxi squad before their 4-1 loss to the Reds on Tuesday night at Great American Ball Park. The rookie went right to work, pitched a clean sixth inning in his Major League debut and walked off the mound to a round of fist bumps and congratulations in the dugout.

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“I was happy it was clean. Anytime you can get a clean one, you never complain,” Cederlind said. “The guys were so supportive coming off. I think they know I’ve been waiting for this one. They’ve been joking all week if I’m ever going to get activated. It was cool to see how happy they were for me.”

Cederlind recorded two groundouts and got Jose Garcia to fly out to left field. He threw 14 pitches -- eight sliders and six fastballs, the latter of which averaged 98.2 mph. His second pitch in The Show was a 99.5 mph fastball that Brian Goodwin took for a called strike.

“I think he was pretty amped up,” Shelton said. “He threw the ball in the zone. He got contact, stayed under control. Really positive first outing. I know he’s an emotional kid. For him to have his first outing go 1-2-3 and get contact on all three, I thought it was outstanding.”

The Pirates had to use six relievers while being swept in a seven-inning doubleheader against Cincinnati on Monday, and starter Joe Musgrove exited Tuesday’s game after giving up four runs in five innings. In need of a reliever, the Bucs called upon Cederlind and optioned outfielder Jason Martin to their alternate training site.

“He’s always had a really good arm. When someone can make the baseball do the kinds of things that he can make it do, there’s always hope and [belief] that that’s going to translate into success against the best hitters,” general manager Ben Cherington said. “There’s kind of no hitter he shouldn’t be able to get out if he’s able to get his pitches where he wants them.”

As the Pirates plan for next year and beyond over the final two weeks of the season, they’ll look for silver linings and signs of hope in young players like Cederlind. His debut was the highlight of the Bucs’ seventh straight loss, in which Musgrove gave up three runs in the first inning and Pittsburgh’s lineup managed only five hits while striking out nine times.

Cederlind, 24, had an excellent Spring Training showing beyond that first live BP session. In five appearances, he struck out nine and walked four without giving up a hit in 4 2/3 innings before he was optioned to Triple-A on March 9. Pirates broadcaster Michael McKenry even dubbed him “Baby Thor.”

The distinguishing blonde hair was gone on Tuesday, cut off the day he reported to the club’s alternate training site, but Cederlind’s stuff was not. He fired fastballs up and away along with sliders down and in, inducing hard contact that was hit directly at second baseman JT Riddle and left fielder Bryan Reynolds.

“He's a really fun guy to watch pitch, and his mentality and his attitude's infectious,” said Musgrove, who struck out eight on the night. “He's a guy we've been waiting on a long time to get up here, and we'll see what he's got, and hopefully he can bring a little spark and a little energy to the team.”

After turning his flat four-seam fastball into a triple-digit sinker, Cederlind soared up the Pirates’ Minor League system. Last year, he posted a 2.28 ERA and a 1.18 WHIP while striking out 55 in 59 1/3 innings as he climbed from Class A Advanced Bradenton to Triple-A Indianapolis. He was bound to reach the Majors at some point this year.

The Pirates invited Cederlind to their Summer Camp workouts at PNC Park, but he was not able to participate after testing positive for COVID-19. They brought him along slowly when he finally reported to their alternate training site in Altoona, Pa., exercising caution rather than rushing back a pitcher who relies on his triple-digit fastball to be effective.

“It just took some time to build the throwing volume up,” Cherington said. “Once he got to that point, probably within the last few weeks, he’s been able to focus again back on execution of his pitches and getting his stuff in the zone. That’s the big thing with him. His stuff is so good that it’s really getting it in the strike zone, being aggressive with it.”

Cederlind has been traveling with the Pirates on this road trip as part of their taxi squad. He threw a bullpen session in Kansas City over the weekend in front of pitching coach Oscar Marin and bullpen coach Justin Meccage, who moved him to the middle of the rubber to give him more freedom on the mound. While Cederlind lingered on the taxi squad, a few of his teammates jokingly asked if he’d get to join the active roster before the season ended. He was wondering, too, until Tuesday afternoon.

“I had a good feeling last night,” Cederlind said, “then I got here today and got the good news.”