Former Illinois tennis star Amer Delic cut an improbable swath through a loaded draw at the Sony Ericsson Open in Miami this week, knocking off the No. 4 player in the world before finally falling in the fourth round.

It was the best professional result of Delic’s career and the best ever by a former Illini player. And it was made all the more unlikely by the route Delic had to take to get there – he had to win two matches just to qualify for the tournament, then upset two higher-ranked players before shocking Nikolay Davydenko, one of the best players on the planet.

“It was a pretty successful week,” Delic said. “(The win over Davydenko) made some waves through the tennis world. It was pretty cool walking into the locker room after the match and (world No. 1) Roger Federer is sitting there and he says ‘nice job.'”

Davydenko seemed in relative control early against Delic, going up a break in the first set and getting a set point on his own serve. The elder player hit a shot within inches of the boundary that was called in, but Delic immediately used the controversial instant replay system to challenge the call.

If the call had stood, he would have lost the first set; instead, the computers showed the ball just missing the line, giving Delic the point and new life in the set. He broke Davydenko minutes later and never looked back, winning 7-6 (5), 6-3.

“I immediately called it out, literally as it landed,” Delic said. “There was absolutely no second-guessing myself right there. Thankfully, it ended up being the right decision. If I was on any other court (without replay), bam, I’m down a set, 6-4. Because of that technology, I was able to reverse the call and have it go my way.”

The Sony Ericsson Open is one of the most prestigious events in tennis, sitting just below the four Grand Slam tournaments in terms of sheer scale. All of the best players in the world come to the event, and Delic finished in the top 16 by making it to the fourth round of competition.

After beating Davydenko, Delic had plenty of chances against Juan Ignacio Chela, but could not upset his third seeded player in a row. Counting his qualifying matches, the 6-3, 6-2 loss was Delic’s sixth match of the tournament, compared to just three for Chela.

“It can take a toll, but by no means was I feeling tired out there,” Delic said. “I was just a little bit off. The score shows three and two, but I had like 13 break points. It could have gone the other way if I make two of those balls, so I left the court with a pretty good taste in my mouth.”

After his performance this week, Delic will not have to worry about extra qualifying matches for a while. His finish should vault him into the top 65 players in the world, easily qualifying him for most major tournaments – including the next Grand Slam event, the French Open in May.