Sorensen was the first player representing Ireland to win a Grand Slam event main draw match in the Open Era.

His father, Sean, was the first Irishman to play a Grand Slam main draw match in the Open Era, going out in the first round of Wimbledon.

[3] Sorensen's father Sean is the current captain of the Ireland Davis Cup team and played in the first round of Wimbledon in 1977, losing to Rod Laver.

[5] Sorensen began his professional career with participation in the France F15 Futures event in Sarreguemines on 25 September, beating Stéphane Piro to reach the 2nd round, before ultimately losing to Riccardo Ghedin.

In February 2007, Sorensen won his first senior international title in the Portugal F1 Futures event in Faro, where he beat Canadian Pierre-Ludovic Duclos in the final 6–1, 6–1.

Sorensen began 2010 by qualifying for his first ATP World Tour 250 series tournament, the first round of the 2010 Aircel Chennai Open, losing to Stéphane Robert 1–6, 2–6.

Sorensen went on to become the first ever player representing Ireland to win a Grand Slam match in the Open Era when he beat Lu in 4 sets, 6–4, 3–6, 6–2, 6–1.

He then faced a length three-month lay-off due to a hamstring injury, but made his comeback on 10 May at the Biella Challenger, defeating qualifier Andrea Arnaboldi in his first round match.

Sorensen's lengthy absence proved his undoing later in the tournament, however, as his lack of match practice showed during his defeat to Yannick Mertens in the second round.

[9][10] However, in June, Sorensen came back from retirement and competed in a Futures tournament in Germany and reached the Quarterfinals before pulling out citing injury.

Because of his significant lay-off from tournament action due to injuries, Sorensen's ranking had slipped to 614 from a career-high position of 213 set in February 2010.

[14] In the final round, Sorensen beat Martin Fischer 7–6, 6–1 to ensure that 2 Irish players, Louk and Conor Niland, qualified for the Main Draw.

He lost his opening match in the Brașov Challenger and then failed to qualify for the Ethias Trophy, losing to compatriot Conor Niland.

In early April he competed in qualifying for the U.S. Men's Clay Court Championships and pushed top 100 player Ryan Harrison all the way in a close three set match but ultimately lost out.

Sorensen then narrowly missed out on making his first ATP Tour main draw since 2011, losing to Mirza Bašić in the final round of qualifying for the Düsseldorf Open.

Sorensen pulled off a shock in the first round, defeating world number 68 Igor Sijsling in straight sets to record his second tour win.