Age championships After learning the game at age six, Láznička won several age-based national championships, including wins in the U10 championship in 1997 and in the U12 championships in 1998 and 1999. He also finished second at the U18 event in 2001 and 4th in the Czech Junior Championship held in Luhacovice in 2003. At the European Youth Chess Championship, held in Herceg Novi in 2005, he was a bronze-medallist in the under-18 category behind Nikita Vitiugov (gold) and Pawel Czarnota (silver). He was unplaced in the 2005 and 2007 World Junior Championships, scoring 7.5/13 on both occasions and scoring 8/13 in the 2008 event in which he was also unplaced.

Tournaments Láznička’s earliest significant tournament success was =1st with Ramil Hasangatin at the Olomouc Valoz Cup 2002, scoring 7.5/11, and 3rd in the 2002 Friendship GM Tournament 2002 in Cartak in the Czech Republic with 7/11, a point behind Andrei Kovalev and Viacheslav Dydyshko. In 2003, he was a joint winner – again with Ramil Hasangatin - scoring 8.5/11 at the Mariánské Lázně Tournament in 2003, =1st in the 2003 Olomouc Open 2003 and =2nd in the Friendship GM tournament. In 2004, he came =2nd with 7.5/11 behind Vlastimil Babula alongside Evgeny Postny in the GM Skanska Cup in Olomouc, Czech Republic, and =2nd with 7/9 in the Czech Republic’s Christmas Tournament behind Pavel Blatny and alongside Andrei Kovalev. He won the Tradefair Festival GM tournament in Brno in August 2005 with 7.5/11 in front of a field of six GMs and five other IMs and went one better in 2006 in Brno when he won the full national Czech Championship with a dominant 8.5/11, 2 points clear of the field. 2006 was also the year he qualified as a grandmaster and started his Olympiad career, scoring the best individual result of the Czech team in Turin.

In 2007, he was joint winner of the Czech Open (with Vlastimil Babula), held in his home town and scored 5.5/9 in his first tilt at the Aeroflot Open A. In the extraordinarily closely fought European Individual Chess Championships of 2007, he scored 7.5/11, a half point behind the 6 joint leaders, and alongside 35 other players who also scored 7.5/11, almost all of them GMs; he also scored 7.5/11 in the 2008 event, but was unplaced, being a point off the lead. In 2008, he shared 1st with Krishnan Sasikiran at Kolkata Open Grandmaster Tournament, winning on tie-break. He then took a share of second place at the EU Individual Open Chess Championship in Liverpool, behind Jan Werle (and equal with Michael Adams and Nigel Short). In December 2009, he tied for 1st-4th with Georg Meier, Julio Ernesto Granda-Zuniga and Kiril D Georgiev in the 19th Magistral Pamplona Tournament. In 2010, he won the City of Good Wine Rapid tournament in Hustopeče, the 38th World Open (2010) with 7.5/9 and the Gyorgy Marx Memorial (2010) with 8/10. His re-entry to competition in 2011 was a relatively meagre affair as he scored only 6.5/11 in the 12th European Individual Championship (2011). However, in July, he performed at rating to came 3rd at the Airports Authority of India (2011) with 5.5/11, behind Fabiano Caruana and Krishnan Sasikiran and repeated his par effort in the Tradewise Gibraltar (2012) where his score of 7/10 reflected his rating. He placed =2nd at the 2013 Dubai Open.

Match In August 2011, he won three and drew three games in the Navara-Laznicka Match (2011). In August 2012, he lost the 6 game Shirov-Laznicka Match (2012) by 4-2 (+0 -2 =4).

World Championship He qualified for the World Chess Cup (2007), but was eliminated in the first round by Bartlomiej Macieja. He made it to round 4 of the World Cup (2009), defeating Ioannis Papaioannou in round 1, Alexander Morozevich in round 2 and Viktor Bologan in round 3 before losing in round 4 to Shakhriyar Mamedyarov.

Olympiad Láznička’s first Olympiad experience was the 37th Chess Olympiad (2006) in Turin where he scored 7.5/10 on board four, just missing out on the bronze. In the Olympiad (2008) in Dresden, he played board 3 scoring 5.5/10. In the Chess Olympiad (2010) at Khanty-Mansiysk, he scored 7.5/11 and came 9th on board 2. He played top board for his country at the Chess Olympiad (2012) in Istanbul, and scored 6.5/11, slightly above a par for rating performance.

Rating His standard rating as of 1 May 2013 was 2679 making him the Czech number 2 and world number 66. He has no rapid rating as yet, but his blitz rating is 2704 (world #34).