Niland spent most of his career on the Futures and Challenger circuits, although he has played a handful of ATP World Tour tournaments.

In Houston, Texas, at the U.S. Men's Clay Court Championships, he qualified for his first ATP main draw but lost in the first round.

[8] After an encouraging start to 2011 saw Niland reach the quarter-finals of the Heilbronn Open in Germany, he struggled throughout the first half of the year with illness and injury and fell to a ranking of 184 by June.

He came into great form for the grass court season, however, and picked up 4 straight wins to qualify for the Aegon Trophy in Nottingham and also defeat 96th-ranked Donald Young in the first round.

He successfully negotiated all 3 rounds, defeating Josselin Ouanna, Greg Jones and finally Nikola Mektić, to qualify for his first ever Grand Slam event.

[16][17] On 12 April 2012, Niland announced his retirement due to a recurring hip injury which resulted in pain and restricted his movement for the previous nine months.

After three years there, Niland went to study English at University of California, Berkeley, before leaving to focus on playing tennis professionally in 2005.

[22] His father, Ray, played at corner back for the Mayo senior Gaelic football team, while his sister Gina is a former Irish No.1 tennis player.