Dan Evans suffered a first-round defeat at the hands of Austrian Lucas Miedler at the Glasgow Challenger in his first tournament since completing a drugs ban.
The 27-year-old had to come through qualifying for the tournament following the end of his 12-month ban for failing a test for cocaine in Barcelona last April.
Evans won two qualifying matches at the weekend, firstly defeating fellow Briton Ed Corrie on Saturday before seeing off Ireland's Sam Berry on Sunday and as a result, and will earn an ATP ranking in the updated standings next week.
The Briton took the first set on Monday but world No 238 Miedler stormed back to break three times as Evans struggled with his match fitness, earning an impressive 2-6 6-2 6-4 win at Scotstoun Leisure Centre.
"I'm not really disappointed, it was a good match, he's better than his ranking I'm sure of that and it was a good level match," said Evans.
"I got a bit tired at the start of the third set and that was it really, (I) lost my serve...just a bit rusty at the start of the third set. But that's a really good game I've just played.
"I played probably the best in that match than all the matches I've played this week, starting to feel the ball way better so I'm looking forward to hopefully playing again soon."
The former British No 2 raced into a 3-0 lead, dropping only three points in the process before Miedler finally got on the board in the fourth game.
The pair shared the next three to give Evans a 5-2 lead, before he completed his second break to win the opening set in 27 minutes.
Evans started the second set with a hold to love but his Austrian opponent rattled off the next three to move in front.
The Briton cut the deficit to 3-2, but Miedler did not look back as he won the next three games to take the second set and level the match at 1-1.
Evans struggled with his serve and fitness as Miedler only needed a solitary break in the deciding set to secure victory.
Coverage of the ATP Madrid Open gets underway on Sky Sports Arena on Monday, May 7 from 11am.
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