Lastin was born in Arkhangelsk and at three years old he moved to Zheleznovodsk.
[1] In 2001 he tied for first with Alexander Motylev in the Russian Chess Championship and finished second on tiebreak.
[3] Lastin competed in the FIDE World Chess Championship 2002, where he was eliminated by Zhang Zhong in round two, after knocking out Ognjen Cvitan in the first.
At the FIDE World Chess Championship 2004 he reached the third round, where he lost to Hikaru Nakamura and therefore was eliminated from the tournament.
[4] Later that year, he placed equal second (third on tiebreak) in the 9th Voronezh Open.
[5] and won the 7th Kuban Championship - Stepanov Memorial in Sochi.
[6] Lastin took clear first place in the Moscow Open 2006 scoring 7½ points out of 9.
[11] In 2008 he tied for 1st–8th places with Nigel Short, Vadim Milov, Aleksej Aleksandrov, Tamaz Gelashvili, Baadur Jobava, Gadir Guseinov and Farid Abbasov in the President's Cup in Baku.
[13] In September 2008 Lastin placed fourth in the Russian Championship Higher League[14] and qualified for the Superfinal of the Russian Championship, where he scored 5/11.
[15] In 2013 Lastin won the Dombay Open edging out Artur Gabrielian on tiebreak.
[18] Russian Championship Higher League 2009, Round 4[19] Ian Nepomniachtchi (2632) vs. Alexander Lastin (2648) 1. e4 c6 2. d4 d5 3. exd5 cxd5 4. c4 Nf6 5.