Career
Thoi is deployed in the central midfield and is known for his stamina, tenacity and ball-winning capabilities. Thoi started his career when representing his state Manipur in the Mir Iqbal Hussain Trophy, a National level under-16 sub-junior trophy. Thoi signed his first professional contract with Chennai-based Indian Bank in 2006 to represent them in the I-League 2nd Division.
Senior His performances with the southern side attracted the interest of Maharashtra-based (now defunct), where he signed a 3-year contract in 2007.
The highlight of his time at Mahindra includes a tournament winning goal in the final of the 2008 Durand Cup against Churchill Brothers. He accepted Bhaichung Bhutia"s inviatiton to play for I-League 2nd Division team, where he stayed for two seasons, appearing regularly in the 2011 season and 2012 season alongside Bhutia, Renedy Singh and Sandesh Jhingan.
While gained promotion, Thoi"s services was enlisted by newly formed Mumbai Tigers, then known as Dodsal Football Club for the 2013 I-League 2nd Division. Thoi became the first player to score for the Mumbai-based team when he scored against Army Red in their first professional game on 25 August 2012 at the Ambedkar Stadium in Delhi in the 2012 Durand Cup.
Thoi scored twice in the tournament as Mumbai Tigers reached the final, but were beaten 3-2 on penalties by Air India.
Thoi would then be picked up by another newly formed Bangalore based team for the 2013-2014 I-League. He would continue with Bengaluru for another season by winning the 2014-2015 Federation Cup before making 16 appearances and scoring 5 times in the 2014-2015 I-League as his team finished runner-up behind Mohun Bagan. Thoi along with Robin Singh and Sunil Chhetri were contracted to the Indian Super League and will be loaned back to for the next I-League season.
He was picked up by Chennai-based for the 2015 Indian Super League for INR 8.6 million during the 2015 ISL Auctions, making him the 3rd most expensive Indian player in the ISL only below his teammates at, Sunil Chhetri and Eugeneson Lyngdoh.
Thoi Singh was called up to the India U19 team for the 2006 AFC Youth Championship held in India between October 29 to November 12, 2006. He made his only appearance as a substitute against Jordan U19s playing as a forward.