The ultimate aim is an Olympic medal, he is still a work in progress but Joseph Schooling's relentless march to reach his goal took another step forward yesterday when he qualified for the 100m butterfly final at the Fina World Championships.

Swimming in his pet event, the Singaporean powered his way to finish fourth in his semi-final and seventh overall while setting a new national mark with a 51.40 sec effort.

That erased the earlier record he set during the heats yesterday morning when he clocked 51.65, which in turn eclipsed the 51.69 national record he set when he won a silver at the Glasgow Commonwealth Games last year.

Quick off the blocks, Schooling switched on his turbo to be the fastest overall at the split in his semi-final (23.83).

But as he bore down towards the wall, he was pipped by a late burst from Hungarian Lazlo Cseh.

But the man to beat tonight in Kazan, Russia, is American Tom Shields, who was timed at 51.03, but who topped the semi-finals ahead of Cseh, although they had an identical time, by virtue of a faster split (23.93 against 24.13).

South Africa powerhouse Chad le Clos was third (51.11).

Schooling now holds national records in seven individual events (freestyle 50m, 100m and 200m; butterfly 50m, 100m and 200 and the 200m individual medley) and as a member of the quartets that have relay marks (4x100m free, 4x200m free and 4x100 medley).

The Singaporean's day began on a high note as he won his heat with a new national record and he was fifth fastest qualifier for the semis.

As a morale-booster, the 20-year-old was faster than le Clos in the same heat, as the Olympic champion finished second with a time of 51.83.

The butterfly specialist's progress to tonight's final caps a fine week for him.

On Monday, Schooling finished seventh in the 50m fly to become the first local man to make the top eight of the biennial world championships since Ang Peng Siong's fourth-place 50m free finish at the 1986 Madrid edition. His time of 23.25 is a new Asian record, which erased the previous mark he set during the morning heats.

A day later, he narrowly missed out on the final of the 200m fly with a time of 1min 56.11sec to finish 10th overall, 0.36sec behind the eighth-placed Shields (1:55.75).

And on Wednesday, he was named Sportsman of the Year at the annual Singapore Sports Awards, his second accolade after his previous win in 2012.

In the women's 50m butterfly heats yesterday morning, Quah Ting Wen finished 37th out of 64 competitors with a time of 27.58.