Tennis-Davis Cup record as Mayer hauls Argentina level in epic

* Argentine wins rubber lasting six hours 42 minutes * 20 minutes longer that 1982 McEnroe-Wilander clash (Adds details, quotes) BUENOS AIRES, March 8 (Reuters) - Leonardo Mayer beat Joao Souza 7-6(4) 7-6(5) 5-7 5-7 15-13 in a Davis Cup singles match that lasted a record six hours and 42 minutes to haul Argentina level with Brazil at 2-2 in their first-round tie on Sunday. Argentine Federico Delbonis led Thomaz Bellucci after taking the first set of the final rubber 6-3 when play was suspended for poor light. The pair will resume on Monday looking to put their country into a quarter-final against Serbia. Mayer won on his 11th match point in a battle of the South American rivals' number ones in searing heat on a purpose-built clay court at the Tecnopolis exhibition complex on the outskirts of the capital. The match lasted 20 minutes longer than a clash in 1982 when John McEnroe beat Mats Wilander in a United States v Sweden quarter-final in St Louis. The longest Davis Cup match was a 2013 first round doubles tie in Geneva in which Czechs Tomas Berdych and Lukas Rosol beat Marco Chiudinelli and Stan Wawrinka of Switzerland 6-4 5-7 6-4 6-7(3) 24-22 after seven hours and one minute. Mayer looked like he might be on his way to a three-set victory when he led 4-1 in the third but Souza recovered, making the most of two double faults by his opponent to take the set, and then won the next to level the match. Mayer had three match points at 5-4, two at 9-8, three at 12-11, another at 13-12 and finally two more, an unreachable return on the 11th finally ending Souza's resistance in the Brazilian's second five-set marathon in three days. Mayer fell to the clay court after sealing the win, but quickly rose and began jumping around with delight and cried with relief. He later needed medical attention for exhaustion. "I don't care about the record ... now we must get behind Fede (Delbonis), we're all a team," Mayer said. "I thank all the people who cheered a lot for me. "It was a battle. If I'd lost it would also have been OK, you give everything on court to try to win." (Reporting by Rex Gowar, editing by Tony Jimenez/Peter Rutherford)