The 35-year-old defender was hired on January 8 by new Toronto president and general manager Kevin Payne while still under contract with QPR.
With the English Premier League side struggling to avoid relegation it was widely speculated that Nelsen would see out the remainder of his contract, which runs until May 19 the end of the English season.
However, it seems he has reached an agreement with QPR boss Harry Redknapp which allows him to get his new career underway before the MLS season starts on March 2.
Nelsen has also decided to call time on his international playing career, meaning he will not be available to help lead the All Whites in the next FIFA World Cup qualifiers against New Caledonia and the Solomon Islands scheduled in March.
The former All White captain, who announced the news this afternoon, retires with 49 ‘A’ international caps for the All Whites after making his debut in 1999.
His last match with the team came against Tahiti in his hometown of Christchurch in October last year.
Nelsen says the decision to end his playing career with the All Whites comes after much consideration.
“Every time I pulled on a New Zealand shirt with the fern on my chest it was a very proud moment for me and I will miss it,” Nelsen says.
“When you’re not enjoying the playing side as much as other aspects of football, you know it is time to move on. That time is now and I want to commit all my energies into my coaching career with Toronto FC.
“I wish Ricki and the team all the best in the lead up to the World Cup qualifiers in March and hopefully, the playoff matches later this year. I believe that I leave the team in a good space with quality players able to carry on the recent success the All Whites have enjoyed.
I’d like to take the opportunity to thank New Zealand Football for their support through this decision making process and all the coaches, staff and teammates I have played for and with over my international career.
“I would also like to thank the New Zealand public for the tremendous support they have given me personally throughout my playing career and for their support of the All Whites and football in general.”
Nelsen has already started making his mark his new side in the pre-season.
The MLS SuperDraft got underway on January 17 and Toronto FC has added a number of new players to their ranks, including 23-year-old New Zealander Nik Robson.
The former Macleans College midfielder spent three successful years at UCF before joining the University of New Mexico for the 2012 season.
He was picked up by Toronto in the third round of the MLS Supplemental Draft on Tuesday January 22.

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