DAYTON, Ohio - The build up to Pitt’s First Four showdown with Mississippi State was all about the playing status of starting center Federiko Federiko. The 6’11” sophomore was deemed a ‘game time’ decision by Jeff Capel on Monday.

The Panthers knew they would be up against on Tuesday against Mississippi State and star big man Tolu Smith with or without Federiko in the lineup. The 6’11” senior was an All-SEC first team selection this year, but not having Federiko to combat Smith inside was certainly going to create a mismatch.

It also created an opportunity for an unlikely hero making his NCAA Tournament debut.

Guillermo Diaz Graham was averaging about 10 minutes per game of playing time heading into Tuesday night, but he did piece together a career performance against Duke in the ACC Tournament. Diaz Graham scored 14 points and grabbed 8 rebounds, but the outcome in Greensboro sort of overshadowed how he played.

It seemed all along the Pitt team knew Federiko would not be able to play on Tuesday but played it close to the vest. Diaz Graham said he knew he would be starting against Mississippi State in the team's morning shoot-around and prepared himself all day for a battle with one of the SEC's top players.

“You've always got to be ready to step in and help the team,” the freshman big man said after Pitt’s narrow 60-59 win. “And hopefully for next game, Fede can be back so he can experience this thing, too, because he was part of the whole year, and now he couldn't play the first time.”

Diaz Graham’s stat line won’t jump off the page, but his defensive approach and effort were noticeable all game long, especially in the second half. The 7-footer posted only three points, five rebounds and two blocks in 37 minutes of action, but his defense against Smith was gritty and heroic for a player who has never logged starter's minutes and was playing in the NCAA Tournament for the first time.

Diaz Graham, a native of Spain, said he did not watch the NCAA Tournament much growing up, and got to experience the madness in person for the first time on Tuesday. He admitted he was blown away by the big stage.

“As soon as we walked on the court I went to (Aiden) Fisch and I was like, ‘Fisch, why are there so many people here? And he was like, ‘March Madness baby, that’s how it is.’"

Smith finished with 13 points on 5-of-11 shooting and had to earn everything he got with the much leaner Diaz Grahm draped all over him throughout the game. The Bulldogs' star player turned the ball over five times with Diaz Graham’s length causing him issues.

“Man, I'm exhausted,” the Pitt freshman said after going toe to toe with Smith. “That was a hell of a fight. He's a really good player, and he was trying to attack me every time. Of course he's bigger than me. Just fighting, he's bigger than me but I'm going to fight more than you. It's exhausting, but we won, so it was worth it.”

The game certainly was not perfect for Diaz Graham, far from it.

The freshman was just 1-of-8 from the floor. The Bulldogs controlled the glass and out-rebounded Pitt 49-28. Despite some mistakes by the young post player, Pitt coach Jeff Capel took note of how his teammates kept his spirits up throughout the game.

“There were times when he wanted to put his head down, that he didn't feel good about maybe an assignment or missing a shot,” Capel explained after grabbing his first NCAA Tournament win at Pitt. “And those guys kept telling him, 'Don't do that. We've got your back, we're with you.' It's who they've been all year.”

Pitt has taken a team-first approach all season and have had multiple contributors, sometimes different ones, in nearly every win this season. The veterans on Pitt’s team rallied around each other, and Diaz Graham, with Federiko unavailable.

“We just wanted to be there for our brother,” Pitt guard Jamarius Burton said of his freshman teammate. “We understood the type of battle he was going to be in, all-conference type of guy, that he was going to be going against, so we just wanted to have his back out there.”

Diaz Graham played Smith tighter as the game went down the stretch. He also seemed to play with more confidence as well. Smith was 3-of-8 in the second half and committed four turnovers.

“Again, for a freshman to step up on this stage and to play like he did, five rebounds, two blocks, his ball screen defense at the end, for the last, I'd say, about eight minutes, we tried to trap every ball screen with the 5,” Capel said of Diaz Graham’s play. “And for him to be able to do that and get back in there and to fight and to battle, this is the most minutes he's played all year, and just really, really happy for him.”

The biggest and most memorable play for Diaz Graham came in the final moments of the game. With Pitt clinging to a one-point lead on Mississippi State’s final possession, Smith attacked the freshman, but Diaz Graham swatted his shot out of bounds and showed off some emotion following the huge, game-saving block.

“Just all the energy coming out of my body,” he said of the emotional moment. "I did a block, I don't even know how, with my left hand. I usually don't use my left hand. And I blocked it, and I knew it was a big play, so I just let the energy go out.”

The Panthers escaped with a one-point win, as the Bulldogs' final attempts were off the mark. It was a joyous scene on the court following the win, and Guillermo found his brother, Jorge, at mid court as the twins shared an emotional embrace.

Jorge only played four minutes in the game, but was the first person to greet his brother after a Herculean effort against one of the better post players Pitt faced all season.

“We knew coming into this game we needed him because Fede was out for us in this game, so we were putting a lot of confidence in him,” Jorge said of his brother’s performance. “He fought. I think he fought the whole game, he did good things, he did bad things, but overall I’m so proud of him and the whole team we’re so proud of him because what he did today as a freshman is awesome.”

Guillermo was asked about that hug with his brother on the floor.

“Just after the shot clock sound and he come to me and hug me, all the emotions I've been feeling during the game,” he explained. “I’ve got to keep my face straight, all the emotions at the end. When I hug him, they just come out, and it's a great feeling.”

The Panthers will continue to need Diaz Graham to play a huge role as they get set to face Iowa State in Friday's first round game in Greensboro. It is possible Federiko could return to the lineup for the Iowa State game, which would be a big boost for the short-handed team.

“There's a chance he could be ready for Friday,” said Capel. “We're very, very hopeful.”

The NCAA Tournament has always been about buzzer beaters, big upsets, and unlikely heroes emerging. It’s early in the Big Dance, but Diaz Graham had one of the tournament’s biggest performances thus far according to his teammate Blake Hinson

“That was probably one of the most impressive stories of the day, honestly,” Hinson said of Diaz Graham. “Coming in out of the blue and having to start for somebody that just got hurt and just got called on and having to play a first-team SEC-er and playing the way he did - one of the best stories of the day.”