"There have been plenty of bruises, and sometimes we've had to bang our heads and go back to the drawing board, but after all these years, he's become more and more polished and has matured as an athlete and a person," Coleman says. "All the parts have come together, and he's blossomed into a national-caliber player."

Sidney identifies one match last summer as his quantum leap. Competing at the USTA boys' 18s national championships in Kalamazoo, Mich., he lost the first set of his third-round match, 6-2, and trailed 5-2, 0-30 in the second, two points from elimination.

All five coaches from the colleges where he made his official visits were watching, along with countless others on center court.

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"I just literally took every ounce of drive I had, and I pushed through and stayed focused on each point one at a time," Sidney says. "I just told myself, 'Don't miss and grind it out.' I was able to get it back to 5-5, and [my opponent] got flustered."

Sidney won the second set, 7-5, and took charge in the third, winning, 6-3, to claim the match.

He took away much more than the victory that day.

"I didn't know I could handle pressure that well," Sidney says. "That I could handle that, it gives me confidence for down the road. If I'm ever in a situation like that again, I know from experience that I've come through before. It was a huge breakthrough for me."

Sidney is banking on more breakthroughs.

This summer, along with the juniors circuit, he's competing in International Tennis Federation Futures tournaments to challenge himself against more experienced players.

After making his mark as the most successful boys player in McDonogh's program, Sidney wants to make the same impact at Cornell.

"There was nothing at Cornell I didn't love," says Sidney, who also considered Harvard, Dartmouth, Notre Dame and Columbia. "My visits were amazing. The campus was great, the coach [Tony Bresky] is a big reason why I looked there, the team was amazing, the academics, the food … just everything was great."

Bresky, who comes to Cornell this year after eight years as an assistant at Virginia, has brought in a recruiting class ranked fourth nationally by Tennis Recruiting Network. And he's glad Sidney is a part of it.

"Alex is a great competitor," Bresky says. "He's really fast and skilled and has a great heart and mind for the game. We're definitely looking for kids who are hard working and passionate about playing tennis and wanting to improve. At Cornell, we're trying to build a top national level program, and I think Alex fits into that."