© Peter Staples/ATP World Tour

Ryan Harrison hits a forehand during his match with Michael Venus against Jean-Julien Rojer and Horia Tecau on Thursday.

Harrison/Venus Complete Perfect Run Through Group Eltingh/Haarhuis

The American-Kiwi duo will play the second qualifier from Group Woodbridge/Woodforde

Ryan Harrison and Michael Venus arrived at The O2 with little to no momentum from the end of their regular season, losing five of their final six matches.

But that has not mattered this week at the Nitto ATP Finals. Harrison and Venus finished round-robin play with a perfect record on Thursday, defeating third-seeded Jean-Julien Rojer and Horia Tecau 6-3, 7-6(5).

"It's been a fun week," Harrison said. "We played a great match the first match and we were just hoping that as the week went on we were able to keep playing in good form and we've been really fortunate to keep playing well."

The American-Kiwi pairing has won Group Eltingh-Haarhuis, and will play the second qualifier from Group Woodbridge/Woodforde in Saturday’s semi-finals.

"Starting again in the semi-finals it's a level playing field for everyone and everyone in this tournament is great so we're going to have to play well," Venus said. "But hopefully we can use some of the confidence from our first three matches out there and keep going."

Rojer and Tecau, the 2015 Nitto ATP Finals champions, finished their season finale 0-3. It is the second time in three appearances in London that this year’s US Open champions have gone winless at The O2, with their career record at the event falling to 5-6.

In the early going, it looked like the Dutch-Romanian team would earn their first victory of the tournament, breaking serve at 2-2. But they could not hold the advantage, losing the final four games of the opener. The eighth seeds proved to have too much power, especially Harrison with his overwhelming serve and forehand, which dominated in the key moments.

There was only one break opportunity in the second set, so the two sides went to a tie-break. And after capturing a mini-break to catapult to a 4-1 lead, it seemed that Rojer and Tecau would force a decider. But at 5-3, Tecau let a Harrison volley go, incorrectly thinking it might sail long. After Harrison claimed two points on his serve to earn match point, the American split his opponents with a lasered backhand to seal the triumph.

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