Marcotullio is another who has stepped up with the Scottish guard scoring seven points off the bench in Thursday's loss to Finland. He credits Joe Prunty and his staff for guiding their progress, he said: "They've really challenged us mentally. They've thrown a lot of stuff at us and we've had to respond to that challenge. I think we've done a great job so far.
"The coaching staff are great teachers. They slow everything down for you, and even though they expect you to learn fast and on the fly, they really explain the premise behind all the drills they do."
Greece will be GB's toughest foe yet with the former European champions underlining their potential by defeating EuroBasket favourites France, as well as Croatia and Germany, to win a three-team tournament in Strasbourg last week, despite the absence of 2013 Euroleague MVP Vasilis Spanoulis.
Prunty has taken valuable lessons from his team's campaign to date while seeing ample room to take steps forward. But he wants to see signs of progress against one of international basketball's proudest names.
"We're going to have to improve on both sides of the ball," said Prunty. "Greece is an extremely good opponent, but what people need to realise is that just why EuroBasket is as great as it is. Every night, you will face a quality opponent who will move the ball, play good team defence and share the ball.
"Greece epitomises that. We'll have to be ready and be prepared."