JOIN USWinning start for FedEx
The Swiss, competing at the season-ender for the 10th consecutive year, raced through the first set in 21 minutes but world number six Tsonga made sure the capacity crowd got value for money with a stirring fightback.
Federer missed two routine forehands in the third game of the second set to gift Tsonga a break of serve and the French powerhouse suddenly came to life, breaking the Federer serve again on the way to levelling the match.
The decider went with serve until the final game when Tsonga wavered badly, missing a routine volley, then serving a double fault to give Federer sight of victory.
A crunching forehand brought up three match points for the 16-times Grand Slam champion and although Tsonga saved one with a first serve winner he could only watch as Federer rolled a backhand winner down the line on his second attempt.
Federer, whose world ranking has slipped to four after a rare season without a grand slam silverware, will set a new record if he retains the title in London.
The 30-year-old is currently level on five with Ivan Lendl and Pete Sampras.
Meanwhile, Rohan Bopanna and Aisam-ul-haq Quershi began their campaign with a
defeat against Daniel Nestor and Max Mirnyi, albeit after a good fight in a Group ‘B’ match.
Fifth seed Indo-Pak pair lost 6-7 (2-7), 6-4, 9-11 to third seed Canadian-Belarus combo in one hour and 41 minutes.
Bopanna and Qureshi will now have to win the remaining two matches in their group to be in contention for a spot in the semifinals. Bopanna and Qureshi even had a set point in the 10th game of the first set but squandered the opportunity.
It was a good comeback as they were down 2-4 at one stage but won three games on the trot to take a mini 5-4 lead.
Leander Paes and Mahesh Bhupathi will compete in Group ‘A’.