Le Clos thrilled to back with the 'top dogs' in Doha

Chad le Clos last mounted a long-course world podium in 2019 but South Africa's most decorated Olympian took a big step toward another in Doha on Friday.

The 31-year-old veteran won his 100 metres butterfly semifinal at the Aspire Dome pool to qualify fifth for Saturday's final and enjoy a big confidence boost as he builds toward the Paris Olympics.

"I'm clearly not the favourite for tomorrow ... But just grateful to be in the final again and up with the top dogs," the four-time world champion told reporters.

"Obviously it's a stepping stone towards the Paris Games, you know, that's where we're looking to surprise."

'WOULD CUT OF PINKY FOR A WIN'

In his pomp, Le Clos famously took the 200m butterfly gold medal off Michael Phelps at the 2012 London Olympics.

Four years later at Rio, Le Clos faded to fourth in the re-match won by the American great and was in a three-way tie with Phelps for the 100 butterfly silver.

Le Clos, who will turn 32 in April, hopes to knock Phelps off his perch as the oldest swimmer to win a butterfly gold at an Olympics.

First off, he needs to put in a big 100m butterfly final on Saturday, which sees Portuguese 19-year-old Diogo Ribeiro top seed.

In the absence of world champion Thomas Ceccon, Ribeiro took the 50m butterfly gold in Doha, improving on his silver from last year's event in Fukuoka.

"Obviously I'm looking for a medal, a medal would be amazing," said Le Clos.

"I'd cut my pinky (finger) off to win tomorrow. I mean, that's just the truth.

"I know people think it's in February and it's not important, but it's important to me and my family and my legacy."