World number one Roger Federer was upset in the Estoril Open semi-final as he again fell short of a clay court tournament victory.

Switzerland’s Federer, who won the Portuguese event in his only previous appearance in 2008, was beaten 6-2 7-6 by defending champion Albert Montanes of Spain in one hour 21 minutes, in a match that many would have bet their scratch cards on federer winning.

Montanes will meet home favourite Frederico Gil after his 6-2 5-7 6-3 defeat of Spain’s fifth seed Guillermo Garcia-Lopez saw him reach his first ATP Tour final.

Top seed Federer, who received a first-round bye, claimed victory over Germany’s Bjorn Phau and France’s Arnaud Clement but was stopped by fourth seed Montanes, the world number 34.

Federer had won the pair’s three previous meetings, two on clay – but Montanes did take the Swiss to four sets at Roland Garros two years ago.

The Spaniard claimed his revenge today as Federer was eliminated early at a second straight clay court event. Federer lost to Ernests Gulbis at the ATP Masters event in Rome last month.

The 28-year-old begins his defence of his French Open title later this month.

Gil, who lost to Federer in Estoril in 2008, was the first Portuguese player ever to reach the semi-finals of the tournament and he went one better with victory today.