British teenager Laura Robson made a bright start but lost on her WTA Tour debut against Iveta Benesova.
Robson, 14, became the youngest Briton to play in a main tour event but went down 1-6 6-2 6-3 to the 25-year-old world number 42 in Luxembourg.
The Junior Wimbledon champion is ranked 550 in the world and was given a wildcard into the Fortis Championships.
"It's been really good and everyone's so friendly on the tour," Robson said after her defeat.
I had a chance to meet Laura and she seems very professional for her age
"It's just been a really good experience. I started off really well and then in the second set maybe it didn't go as well as I planned, but then she started playing better as well.
"It's a tough loss but I still felt I played good."
Robson had played three events on the second tier of professional tennis before Luxembourg and will now return to junior tennis.
She made her debut on the International Tennis Federation's circuit in France in September, where she won her first match, and also competed in Shrewsbury and Barnstaple.
Robson does not turn 15 until 21 January 2009
Her best performance came in Shrewsbury, where she beat three opponents to reach the semi-finals, and she then lost to Germany's Angelique Kerber in the first round in Barnstaple.
Robson's performances have already caught the attention of some of the world's leading players, among them French Open champion Ana Ivanovic, who has met the Briton twice in the last year.
"I think she's great, she has so much potential and she's only 14 and hits the ball really, really hard," Ivanovic told BBC Sport on Tuesday.
"She won Wimbledon juniors and has also played against some WTA players before and is obviously getting more experience. I think she's definitely one to look for.
"I think she just needs to be determined and motivated to keep improving and not get satisfied with what she has, but I had a chance to meet her and she seems very professional for her age, very determined and a very nice girl, so I think she's going the right way."
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