Great Britain's women hockey team's 20-year wait for a Olympic medal continues after Argentina set up a final with Netherlands following a tense semifinal at the Riverbank Arena.
First-half goals from Noel Barrionuevo and Carla Rebecchi gave the Argentines a half-time lead, as Team GB struggled to make an impression.
Alex Danson did halve the lead with five minutes remaining, leading to a deluge of late pressure, but the side ranked No.2 in the world held out to book a final spot against the Netherlands, while Great Britain will contest the bronze final against fellow beaten semifinalist New Zealand.
"We just ran ourselves into the ground to go for that win we knew what we had to do," Emily Maguire said. "We worked so hard for 70 minutes, but it wasn't quiet there.
"All through the game, a lot of the team believed we were going to win it and we were going to be in that gold-medal match. You can't ever go into a match not knowing you were going to win, and we believed all the way and unfortunately."
"We conceded that early corner, and it was always going to be an uphill battle from there," Laura Bartlett added.
"We were never going to give in, and unfortunately Alex's goal came a bit too late, and there wasn't enough time on the clock for us to keep going."
"We were building momentum throughout the whole of the second half, and it was only a matter of time.
"We knew every game was going to be difficult and, yes, were up against it in the China game, but I don't think it disrupted us. We were always focusing on each game at a time, and we knew Argentina were going to come at us hard, and we fought right to the end, but it wasn't enough."
The second women's Olympic semifinal was a repeat of February's Champions Trophy final, with group A runner-up Great Britain taking on an Argentina side that topped group B.
Having qualifed despite two successive defeats at the end of the group stage to China and group winners the Netherlands, GB was looking to produce a performance worthy of its pretournament status as potential medal contenders.
However, they got off to the worst possible start as Barrionuevo netted from a penalty corner inside six minutes.
The hosts were again failing to get Helen Richardson and Danson involved in attacking areas, but the latter almost yielded an equalizer when her reverse hit rebounded against the side netting.
The rare foray in the Argentine half only worked as a temporary respite for Britain, who contrived to allow Rebecchi to trick her way through, around Beth Story, before poking the ball over the line while lying on the ground.
With a medal guaranteed if victorious, Britain threw everything at Argentina in the second half, with Richardson failing to hit the target for their best effort after the interval.
With five minutes remaining, Danson did halve the deficit from close range after Richardson's driven cross, leading to a late onslaught from the home side.
But if Danson's goal was meant to be the precursor to a late Great Britain salvo, it wasn't to be as Argentina progressed to the gold medal final against the Netherlands, with Hilary Rose's side take on New Zealand in the bronze final.