MELBOURNE, Jan 20 (Reuters) - British teenage tennis star Emma Raducanu was unable to find the solution to her latest Grand Slam puzzle on Thursday, as a combination of a blistered racket hand and an inspired Danka Kovinic derailed her Australian Open plans in the second round. The 17th seed, who rocketed to fame by winning last year"s U.S. Open as a qualifier without losing a set, gritted her teeth through the discomfort to stay in contention in a tense clash but fell to a 6-4 4-6 6-3 defeat. Nineteen-year-old Raducanu, who beat former U.S. Open champion Sloane Stephens in the first round to take her Grand Slam main draw record to an incredible 11-1 from three events, needed treatment after the fifth game of the first set. With her hand taped she was unable to deliver her usual baseline power and resorted to slicing virtually every forehand. Incredibly she turned the shot of choice for many a club hacker into a weapon and at times the 98th-ranked Kovinic seemed at a loss to know how to handle it. But the 27-year-old Montenegran showed great composure to dominate the deciding set and move into the third round of a Grand Slam for the first time in her career. Raducanu was still smiling as she congratulated her opponent at the net and while the loss will sting like her blistered hand for a while, she will look back with few regrets and will regard the match as part of her steep learning curve. She also now knows she has a tricky sliced forehand option for emergencies. "I was struggling with my hand before the match. There were some people in my team that maybe didn"t want me to play, but I wanted to go out there and fight through it," Raducanu said. "I thought it was a pretty good learning experience for me. I discovered tools about myself and my game that I didn"t know I had before. I can take some positives even from this match." There was little hint of the problems to come as Raducanu came out firing on a warm evening on Margaret Court Arena, breaking her opponent"s serve twice to lead 3-0. Kovinic soon settled down though and began to strike the ball with menace as she took the next two games. At the changeover Raducanu, who played only one match in the build-up to the Open and lost that heavily, asked for a medical timeout to have her blisters treated and tape applied. It clearly hampered her, especially on the forehand, and Kovinic won the next three games to lead 5-3. Raducanu managed to break serve again but Kovinic replied immediately to take the opening set. Bizarrely, Kovinic kept hitting to Raducanu"s backhand side in the second set and got increasingly tight, dropping serve at 4-4 as the match went into a decider. Despite the blisters and lack of experience, Raducanu looked like the favourite as the third set began. But Kovinic dug deep to keep in front at the start of the decider with some aggressive hitting, and Raducanu looked weary as she slipped to 2-5 down. Serving for the match at 5-3, Kovinic saw one match point disappear as Raducanu belted a forehand winner, but she converted the second with a stunning backhand down the line. "When she changed her game a little bit, I got confused, like what"s going on?" said Kovinic. "When I started just to focus on my own game, then I found composure again and things got better."