Swiss fifth seed Stanislas Wawrinka fluffed two match points at his home tournament on Monday, crashing out 3-6, 7-6, 7-6 to Germany's Benjamin Becker in the first round of the Swiss Indoors.
It was the second time this month that Wawrinka had been beaten by a German qualifier, having also lost at the same stage of the Vienna Open to eventual tournament winner Philipp Petzschner.
With Basel-born top seed Roger Federer not due to start his bid for a third successive home town title until Tuesday, world number 12 Wawrinka had seemed ready to provide local supporters with the perfect warm-up act on Monday.
After easing through the first set with two breaks of serve to one, however, the Swiss number two endured a dramatic turn-around while serving for the match at 5-4 in the second.
Within two points of victory at 30-30, Wawrinka was wrong-footed by a couple of powerful Becker winners and then outplayed as the German world number 137 edged the tiebreak 7-5.
The third set was an even messier affair with Wawrinka breaking ahead twice and twice being broken back.
He then failed to convert two match points in Becker's final service game, paying the price as Becker coolly clinched the tiebreak, 7-5 again, for the match.
"It was tiredness. I'm feeling tired physically and mentally now it's near the end of the season," said Wawrinka, whose latest defeat has all but ruled out his chances of qualifying for the season-ending Masters Cup.
"I was missing shots that I would have made earlier in the year. Of course, it's frustrating to lose after being ahead but Becker also took more risks when he was behind and so deserved the win in the end."
Swiss wildcard and Basel native Marco Chiudinelli suffered a much more expected first round exit earlier in the day against Spanish world number 39 Feliciano Lopez.
Chiudinelli, unranked after a year out injured, came surprisingly close to an upset, however, eventually going down 7-6 7-6.
Russian sixth seed Igor Andreev also came through a tough first round encounter to beat Austrian world number 35 Juergen Melzer 7-6 7-5.
Compared to his fellow top players, American eighth seed Mardy Fish enjoyed a relatively easy opening day, seeing off Argentina's Agustin Calleri 7-6 6-2.