text: Media playback is not supported on this device
  GB had opened their campaign with a comfortable 31-7 win over Kenya, Dan Bibby (2), Dan Norton, Phil Burgess and Mark Bennett all scoring.
  Against Japan - who upset joint favourites New Zealand 14-12 - GB led deep into the final stages.
  But Japan scored a third try, only to miss a conversion to draw with time up.
  Media playback is not supported on this device
  New Zealand - who will be without Sonny Bill Williams for the rest of the tournament after he partially ruptured an Achilles tendon - bounced back from their shock opening loss to Japan to beat Kenya.
  Augustine Pulu scored 11 points, including three conversions, as the All Blacks recovered from conceding a try inside the first minute to win 28-5.
  Team GB only just maintained their 100% start to the tournament when they met Japan, James Rodwell scoring twice and Marcus Watson adding another with captain Tom Mitchell converting all three tries.
  The Japanese could have drawn after the final hooter when Lomano Lemeki crossed for Japan's third try, but Katsuyuki Sakai missed the tricky drop-goal conversion.
  Britain face New Zealand at 16:30 on Wednesday in the final match in Pool C.
  The top two sides in each of the three pools go into the quarter-finals, plus the two best third-placed teams.
  Media playback is not supported on this device
  Feel inspired to have a try? Here's our handy guide.
target: Britain's men made it two wins from two in the Olympic sevens as they edged past New Zealand's conquerors Japan 21-19 in a thriller in their second match.