Great Britain's return to the international stage after 12 years away ended in 14-6 defeat by a Tonga Invitational XIII in Hamilton, New Zealand.
BBC sports reports Michael Jennings' opening score and a stunning Sione Katoa try just before half-time put the Tongans 12-0 up at the end of a bruising first period.
Suo Siua Taukeiaho's penalty added another two points to the lead.
John Bateman's try provided some hope, but it could not prevent the Lions' four-game tour starting with a loss.
The Great Britain side is back on the international scene after more than a decade's absence.
Since the Lions last played in 2007, England, Scotland, Wales and Ireland have competed under their own banners - and will continue to do so at future World Cups.
BBC
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