Feliciano Lopez, who had been handed the awesome task of replacing injured world number one Rafael Nadal, stormed to Spain's rescue on Friday when he leveled the Davis Cup final against Argentina. The stylish left-hander defeated Argentine number one Juan Martin del Potro 4-6, 7-6 (7-2), 7-6 (7-4), 6-3 to make the score 1-1 after David Nalbandian had put the home side ahead with an easy 6-3, 6-2, 6-3 win over David Ferrer in the opening singles rubber. Lopez overcame a passionate 11,000-strong home crowd at the Estadio Islas Malvinas to see off the 1.98m (6ft 6in) giant Del Potro, the world number nine, who ended the match with a crippling groin injury which could rule him out of Sunday's reverse singles. Del Potro, who had secured Argentina's final place with a live fifth rubber win over Igor Andreev in September's semifinal against Russia, had cruised through the first set with a break in the fifth game. But Lopez, seven years the Argentine's senior, then took two nerve-tingling tie-breaks, defying the wild support of the local crowd who were repeatedly warned by the umpire to curb their enthusiasm. Del Potro hurt his groin to go 2-4 down in the fourth set and he never recovered with Lopez taking the match after 3hrs 20mins when the home player netted a comfortable forehand. Earlier, Nalbandian had little trouble seeing off the highly-strung Ferrer to give Argentina a boost in their bid to win a first ever Davis Cup title. “I played a very good match. I was very solid from the first point and I was playing at a very high level,” said Nalbandian who had gone into the match with a 3-6 record against Ferrer but has now won 14 Davis Cup rubbers at home. “It was a short match (just over two hours) so that's good for the rest of the weekend.” Nalbandian also praised the crowd who weren't required to hit full fever pitch with their man in total control of proceedings. “They were fairly calm but when we need more support we will get it.” Argentina lost both of their previous Davis Cup final appearances - in 1981 against the USA and 2006 to Russia. The South Americans have won their last 13 home ties in the competition with their last defeat coming in 1998 against Slovakia. Spain is appearing in its sixth Davis Cup final having won the title twice, beating Australia in 2000 and the United States in 2004.