The 17-year-old youth on the other side of the Wimbledon net looked like an easy match-up for Jiri Novak, but the five-setter made the grizzled Czech rethink the man who would become "exceptional and an icon".
Novak could breathe a sigh of relief as the scoreboard said he had beaten a certain Roger Federer of Switzerland 6-3, 3-6, 4-6, 6-3, 6-4 after two hours and 18 minutes in the first round in 1999.
Federer made his Wimbledon debut that day 20 years ago but few imagined that the youngster would eventually go on to be widely regarded as the greatest player of all time.
"I was in the top 100, I had no problem qualifying for Wimbledon and I played against Roger who was a junior and a wild card," Novak told AFP.
"I was thinking -- what a great draw, I wasn't too good on grass so I thought this was a good chance to win a match," added Novak, who was 24 at the time.
He bowed out of that edition of Wimbledon in the second round, seen off by American Todd Martin in straight sets, and was never to make it past the third round at the All England Club.
Federer, the world junior number one in 1999 but 103 in the ATP rankings during Wimbledon, crashed out in round one in three of his first four appearances at the tournament.
However, he made people sit up and take notice when he famously knocked out Pete Sampras on his way to the 2001 quarter-finals.
Federer then won five Wimbledon titles in a row, and eight overall, his last coming in 2017.
"I thought he wasn't bad but during the match I never thought he could achieve what he has," said Novak of a player who has gone on to win 20 majors and 102 titles in total.
"It was a tough moment, the grass used to be much faster so we didn't play much and I didn't like that, I kept struggling for rhythm."
- 'Exceptional, an icon' -
"Then I met him at other tournaments, on concrete and clay, and I could see he's good," added Novak, who won seven ATP singles titles -- four on clay and three on hardcourt -- and climbed to fifth in the world in 2002.
"In total I played against him nine times, including finals at Gstaad and Vienna when he was already the world number one."
Novak had a special relationship with Federer -- not because of that Wimbledon match, but through Federer's wife Mirka, born in Slovakia which formed a single country with the Czech Republic until 1993.
"We had trainings together, we were a bit closer than normal because of Mirka and his Czech physiotherapist Pavel Kovac," said Novak.
"In the players' room, we played table tennis or pool. He was always closer to the Czechs. But we never talked about his Wimbledon debut," he added.
Novak retired from the sport at 32 because of his family, but he stays on as a coach and keeps watching Federer on the circuit.
"I last saw him in the flesh about ten years ago, at a tournament in Miami," said Novak, currently the head coach of Czech under-18 players.
"I follow his results, I don't watch each match he plays, but he's incredible, he keeps winning tournaments at almost 38 years old and he's still among the best in the world."
Asked to pick a favourite among Federer, Rafael Nadal and Novak Djokovic, the former Czech star had no doubt.
"I have played against all three and I know them all and they are all very cool, but Federer is simply exceptional, a real ad for tennis and an icon," Novak said.