At the 2010 Australian Open, he lost in the second round to World No. 2 and defending champion Rafael Nadal 2–6, 2–6, 2–6. At the 2010 French Open, he played and won the longest match of his career in the first round against American Michael Yani with the score at 6–4, 6–7, 6–7, 7–6, 12–10. The 4-hour, 56-minute match stretched over the course of two days, and tied the record for the most games played in the Open Era at the French Open.
Lacko continued his 2nd round streak in 2010 majors by defeating the 24th seed Marcos Baghdatis in four sets. He then lost a very tight five set 2nd round match against Jérémy Chardy.
Won tournament; or reached Final; Semifinal; Quarter-final; Round 4, 3, 2, 1; competed at a Round Robin stage; lost in Qualification Round; absent from tournament event; played in a Davis Cup Zonal Group (with its number indication) or Play-off; won a bronze, silver (F or S) or gold medal at the Olympics; a downgraded Masters Series/1000 tournament (Not a Masters Series); or a tournament that was Not Held in a given year.
To avoid confusion and double counting, these charts are updated either at the conclusion of a tournament, or when the player's participation in the tournament has ended. Current till 2015 Australian Open.