Yelena Soboleva's string of smashing runs continued today with a stellar world indoor record in the 1.500m during the third and final day of the Russian Indoor Championships in Moscow. 

Soboleva, who set the previous world indoor record of 3.58,28 at the Russian Indoor Championships two years ago, knocked 0.23 seconds from her personal best to run her ninth, career sub-4 minute 1.500m and win her second event of the weekend - her third career indoor national title. 

Soboleva, who holds lifetime bests outdoors of 3.56,43 in the 1.500m and 4.15,63 in the mile, became only the second athlete in history to record two sub-4.00 clockings indoors. For comparison, the sub-4.00 clocking has been accomplished 226 times outdoors, with 59 of those by a combination of Russian athletes - including seven by Soboleva.

American Regina Jacobs, third on the all-time list, was the first female under four minutes indoors, running 3.59,98 in Boston, Mass., USA in 2003. Jacobs was subsequently banned in connection with the 2003 BALCO scandal.

Tatyana Kazankina holds the Russian outdoor national record in 3.52,47 set in 1980. 

Soboleva won the women's 800m in a national indoor record time of 1.56,49 on Saturday.

Soboleva, who set a national indoor record in the mile run (4.20,21) on 27-January, is now the fastest Russian ever, indoors at the 800m, 1.500m and mile events.  Soboleva's 800m is fifth on the all-time world indoor list and is a mere 0,67 seconds from the world indoor record. 

Slovenian Jolanda Ceplak, who is currently facing a drug suspension, set the world indoor record of 1.55,82 six years ago in Wien - a race she won by defeating Austria's Stephanie Graf by a scintillating 0,03 seconds.

Soboleva, 25, won the prestigious 800m on Saturday by more than two seconds up on Natalya Ignatova (1.58,84), who set a personal record of her own in running under the two-minute barrier for the first time.

Marya Savinova and Marya Shapaeva both  ran 1.59,71 for third and fourth, respectively, with Shapaeva establishing a new Russian Under-23 national indoor record.

Soboleva ran a very controlled opening two laps of her race, splitting 29,7 for the first 200m, and 28,5 to reach the half-way point in 58,2 - a pace spot-on for a 1.56,4.

Soboleva then peeled off a 28,6 third lap split to reach the 600m mark in 1.26,85, and concluded her historic run with a 29,6 final lap.

Soboleva's 600m en-route time has only been bettered by 10 women in a full 600m race, including Ignatova, who ran a 1.26,53 in Moscow the same evening as Soboleva's national record in the mile. 

Soboleva's 57,1 middle 400m split was a testament to her fitness being at top-level, and sent a clear message that her international rivals will be hard-pressed to sprint past her in the 1.500m, which is 700m further, and averages five seconds slower per lap.