BRITISH number one Cameron Norrie saw off Argentinian Pedro Cachin in three sets in the first round of the Erste Bank Open.

Seventh seed Norrie is still in the running to qualify for the ATP Finals but needs a deep run in Vienna to boost his chances of making next month’s season-ending tournament.

The world number 13 had to fight back from a set down to beat lucky loser Cachin 3-6 6-2 7-6 (1) in over two hours at Wiener Stadthalle.

Norrie will face either Netherlands’ Tallon Griekspoor or American Marcos Giron in the last 16.

Cachin, 42 places behind Norrie in the ATP rankings, recorded 19 aces to Norrie’s seven but the Argentine’s resilience waned as they entered the deciding tiebreak and the Wimbledon semi-finalist prevailed.

Norrie saved a break point in the fourth game of the match as the set remained on serve until the eighth game.

Norrie was up 30-0 but Cachin reeled off three straight points before breaking the Briton’s serve for the first time, and he went on to seal the opening set with his fifth ace.

Norrie opened the second set with a fine overhead to win the first game and he started to chip away at his opponent’s confidence, fending off three break points to win game three before breaking Cachin’s serve for the first time.

The Argentinian clawed back a game but the momentum had shifted and Norrie took the next two games to force a third set.

Norrie squandered three break points in the fourth game and he had two more chances to break his opponent’s serve in game six but could not capitalise as Cachin unleashed his 13th ace of the evening.

Cachin battled his way into a tiebreak but by then his energy had waned as Norrie swiftly raced into a 5-1 lead by the change of ends.

Norrie quickly set up his first match point and, after faulting on his first serve, wrapped up victory with a powerful forehand.