LONDON - Yakov Toumarkin yesterday became only the second Israeli swimmer to reach the final of an Olympic event by finishing fifth in the semifinal of the men's 200m backstroke event. He also equaled the Israeli national record that he had set earlier in the day in the heats - 1:57.33.

Swimming in lane six, Toumarkin got off to a relatively slow start, completing the first 50 meters in a time of 28.02 seconds, leaving him in last place. An even slower second leg (29.79 seconds ) failed to improve the 20-year-old's position, and when he finished the penultimate leg in seventh place, his chances of making the final appeared to have sunk like a stone.

But with the other competitors flagging badly, Toumarkin rose up through the ranks and finished in fifth place in his heat. All that he could do thereafter was wait for the results of the second semifinal, knowing that if fewer than four swimmers matched or bettered his time he would snag a place in the final.

Nick Driebergen of the Netherlands finished fourth in the second semifinal in a time of 1:57.35 minutes - two-hundredths of a second slower than Toumarkin - giving the Israeli swimmer a place in tonight's final.

Toumarkin, the slowest of the eight finalists, will swim in lane eight tonight. Among the big names he will come up against is American Ryan Lochte, who has already won two gold medals and one silver medal at the London Games and will be hoping to add to his tally.

Toumarkin was not the only Israeli swimmer to make a splash in the pool yesterday. Earlier in the day, Gal Nevo qualified for the semifinals of the men's 200m individual medley, after he finished his heat in fifth place, in the excellent time of 1:59.56 minutes.

In his semifinal, Nevo finished fifth in a time of 1:59.17 minutes, and was bumped up to fourth place when Markus Rogan of Austria was disqualified. Nevo, too, had to wait for the result of the second semifinal, but, unlike Toumarkin, he missed out on a place in the final. His time was only enough for a 10th-place finish, almost a second behind than the slowest qualifier.