© Marcello Zambrana

Daniel Munoz-de la Nava reaches the final of the ATP Challenger Tour Finals following Guido Pella's injury withdrawal.

Munoz-de la Nava, Clezar Advance In Sao Paulo

They say it's not how you start, it's how you finish. 

That has been Daniel Munoz-de la Nava's mantra this week at the ATP Challenger Tour Finals. The Spaniard, who dropped his opening round robin match in Group A to Inigo Cervantes on Wednesday, qualified for the semi-finals with a 4-6, 6-3, 6-2 win over Paolo Lorenzi.

A battle of 33-year-old veterans, Munoz-de la Nava exorcised his demons against Lorenzi having dropped five consecutive matches in their FedEx ATP Head2Head series since 2009. The father of two is projected to rise to a career-high position of No. 80 in the Emirates ATP Rankings with the win.

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Top seed and World No. 68 Lorenzi was eliminated from semi-final contention with the loss and finishes another successful season with a 43-13 record.

In the other Group A matchup, fifth seed Cervantes capped an undefeated round robin campaign, downing Farrukh Dustov 6-3, 6-3 in one hour and 18 minutes. He fired seven aces and did not face a break point. Cervantes remains the 2015 match wins leader with a 48-20 win-loss mark, pulling into a tie for fourth place in the all-time list of most victories in a season.

Meanwhile, Guilherme Clezar qualified for the semi-finals once again, streaking past Radu Albot 6-2, 6-4. The Brazilian home hope was a suprise finalist last year and will look to exact revenge on Cervantes when the pair square off on Saturday. The second place finisher in Group B, Clezar lost to Cervantes in straight sets last week in Montevideo.

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"I have great memories from last year," said Clezar. "The crowd gave me a lot of support today and that is always a great motivation for a player, to be able to feel everyone behind you. I've playing Challengers the whole year, I didn't lose many matches to players with a lower ranking than mine. My level as a Top 200 player is established. I just need to win more matches.

"The situation is different from Montevideo. It was raining there, the serves weren't going that fast. [Cervantes] is someone that counter-attacks really well. I hope the serve can make a difference and my balls can go faster. The conditions here suit me more."

The nightcap at the Pinheiros Club featured a meeting between a 2-0 Guido Pella and 0-2 Marco Cecchinato. Already guaranteed a spot in the last four, Pella's Sao Paulo campaign would come to a heartbreaking abrupt end as the World No. 76 Argentine retired with a torn right adductor. It was the 2012 champion's second leg muscle tear in three years after suffering a torn hamstring at Wimbledon 2013. He led Cecchinato 6-1, 1-0 when the injury occurred.

Pella, who was slated to face Munoz-de la Nava in the semi-finals, concedes the walkover to the Spaniard, who advances to the title match.