[1] Hájek's best result in the World Cup was a fourth place in Tauplitz and Sapporo in 2010.

He held the Czech ski jumping distance record at 236 meters.

[2] Hájek had an accident in Oberstdorf in 2005, crashing in the trial round; he did not suffer major injuries and walked from the hill by himself.

His best finish at the FIS Nordic World Ski Championships was ninth in the team large hill event at Sapporo in 2007.

[6] On 10 March 2023, the Czech Ski Association announced that Hájek had been found dead in Malaysia.