There is, of course, much difference between the three. Fesenko and Koufos have guaranteed contracts while Suton is fighting to make the team as a second-round draft pick. In the locker room, Fesenko is as free-spirited as Koufos is serious.

The biggest question remains whether Fesenko and/or Koufos will prove enough in the preseason to warrant a spot in the Jazz's rotation. They combined for 20 points and six rebounds in Sunday's game, but the results otherwise have been mixed.

"They need to play," Jazz coach Jerry Sloan said, "and it's good for them to get a chance to play and have some opportunities to make some mistakes and have something good happen for them."

Only a day earlier, Sloan described Koufos and Fesenko as being "nonexistent" in the Jazz's loss to the L.A. Clippers, opting not play either in the second half. Both bounced back against Charlotte, helping the Jazz pull away in the fourth quarter.

Koufos had a three-point play putback and hit a tough turnaround over DeSagana Diop with 3:42 left. Fesenko had a tip-in followed by two dunks and finished with 11 points.

He had scored in double figures only once before in the preseason and once in the regular season. Fesenko even converted a three-point play at the foul line in the second quarter. "After I hit that free throw, I was the luckiest guy in the world," he joked.

Asked about the importance of proving he belongs in the rotation, Fesenko answered, "It's the most important [thing] right now for me."

"There is nothing more important right now -- nothing," Fesenko added. "Because after all the [comments] I already did about the breakthrough season, I cannot step back. I can only go forwards. I'm not going to stop. It's going to get only better and better."

Koufos played in 48 games as a rookie, but has struggled at times this preseason. He maintained, though, that he hasn't gotten discouraged.

"I've been focused the whole time," Koufos said. "I'm getting in a rhythm to play and work hard every day and I'm still very confident."

Sloan said both Koufos (20) and Fesenko (22) have improved since last season, adding that it's important to remember just how young they are. He did express disappointment that neither was able to play for the Jazz's summer league team.

While Fesenko opted to play for the Ukrainian national team, Koufos missed all five games in Orlando, Fla., with a dislocated left ring finger. "It takes a lot of time for them to learn all the stuff you're trying to do," Sloan said.

Sloan noted the difficulty for Koufos in learning how to play man-to-man defense with the Jazz after playing in a zone defense during his lone season at Ohio State. "It's a learning process," Koufos said, "but I feel like I can provide for the team."

"He gets frustrated, he touches somebody, he gets in foul trouble and then he feels sorry for himself," Sloan said. "That's when you fight through things. It's like when things go wrong, you've got to fight through it rather than to cave in."

Had he not left for the NBA, Koufos would be heading into his junior season in college. He was the league's second-youngest player last season, but has convinced Sloan that he is willing to work and dedicated to improve.

"I'm sure he wants to do well," Sloan said. "When I've talked to him, he wants to play well. He wants us to get on him, get after him, try to make him better. I probably do it sometimes a little bit to a fault, but he has talent."

The Jazz could send him to the NBA Development League, but with only 13 players including the injured Matt Harpring under contract, Koufos is likely to be in uniform out of necessity if nothing else.

"The way we are now, there's a possibility he probably could play some for us," said Sloan, who noted that Koufos is averaging 4.2 rebounds a game and leading the Jazz with 15 offensive rebounds in the preseason.

Fesenko, meanwhile, will be a free agent after the season, underscoring the urgency after playing in only 30 games his first two years in Utah. He reported to training camp in his best shape yet, but the Jazz still have questions about his seriousness.

Asked if Fesenko had toned down his act, Sloan replied, "Some." He said of the former second-round pick: "You can't jackpot around and get better and he could be a lot better," adding: "He's a big body. We need a big body to try and help us play some."

Carlos Boozer said that while Fesenko and Koufos were talented, hardworking players, they still were learning to play through mistakes the same way as veterans.

"They've just got to stay a little bit more positive," Boozer said, "and don't beat themselves up too much, in my opinion, and keep working, though."

rsiler@sltrib.com Center stage

Kyrylo Fesenko and Kosta Koufos are trying to prove they deserve a spot in the Jazz rotation this preseason. A look at their numbers so far: