Sam Groth stuns Feliciano Lopez to reach Stuttgart last eight

Berlin: Australia`s Sam Groth pulled off a second-round shock at the Stuttgart grasstcourt tournament Wednesday by recovering from losing the first set to beat third-seed Feliciano Lopez in reaching the quarter-finals.

The 27-year-old from Melbourne, who is ranked 66 in the world, dug deep to claim a 3-6, 7-6 (7/5), 7-6 (8/6) win over the Spaniard, who is 14th in the ATP rankings, having held his nerve in a desperately tight third-set.

Groth has the chance to claim another scalp when he faces Serbia`s Viktor Troicki in the quarter-finals.

Eighth seed Troicki needed three sets and exactly two hours to also reach the last eight as he saw off 18-year-old German Alexander Zverev, the youngest player in the top 100, 6-3, 6-7 (6/8), 6-3.

Fourth seed Gael Monfils needed two tie-breakers to force his way into the quarter-finals with a over Austria`s Andreas Haider-Maurer.

France`s Monfils took nearly an hour and a half to seal his 7-6 (8/6), 7-6 (7/5) win and will now face either Poland`s Jerzy Janowicz or home favourite Philipp Kohlschreiber for a semi-final place.

Top seed Rafael Nadal starts his campaign on Thursday with a second-round match against Marcos Baghdatis.