NEW DELHI: Fitness will be the key to cancer survivor Yuvraj Singh's selection to the Indian team for a home Test series against England next month, skipper Mahendra Singh Dhoni said on Wednesday.

“We have to assess whether Yuvraj is ready to field for two days,” said Dhoni when asked whether the skilful all-rounder would be picked for the four-Test series starting in Ahmedabad on November 15.

Yuvraj, who has not played Test cricket since last November, was treated for a rare germ-cell cancer between his lungs in the United States earlier this year.

The 30-year-old returned after chemotherapy treatment in April and played in the recent World Twenty20 in Sri Lanka. He also cracked a double-century in a domestic four-day game in Hyderabad this month.

Yuvraj has performed impressively in the ongoing three-day match against England in Mumbai, scoring a half-century and taking two wickets for India 'A'.

The Indian team for the opening Test will be named on Monday.

“It is very difficult for me to comment on his (Yuvraj) fitness sitting over here. We have to understand that five-day format has its own uncertainties unlike ODIs or T20s,” Dhoni was quoted as saying by the Press Trust of India.

“In ODIs, you know that you have to field for 50 overs only, while in Test cricket there may be a situation that a team might bat for one-and-a-half to two days.

“Having said that it is Yuvraj who is the best judge about how he is feeling. He has played quite a few domestic games now and it is up to him to reflect on his game.”

Yuvraj has played 37 Tests since his international debut in 2000, scoring 1,775 runs at an average of 34.80 with three centuries. He was also named man of the tournament in India's 50-over World Cup triumph last year.