Great Britain hockey coach Danny Kerry was impressed with the character his side showed as they recovered from twice being pegged back - losing a two-goal lead at one stage - by Korea to win 5-3.
Nic White's early opener was cancelled out by Kim Darae before goals from Crista Cullen and then, in the second half, Georgie Twigg and Alex Danson put the hosts in a commanding position.
However, two goals inside six minutes from Han Hye Lyoung and Park Mi Hyun levelled things up only for Twigg and Chloe Rogers to score within two minutes of each other to secure the win which took the team top of Pool A after two matches.
"Everyone knows Korea are serious semi-final candidates and they are one of the teams coaches talk about as they have a lot of threats," said Kerry.
"I was delighted with the way we tried to deal with some of those threats. As I get older I realise it is never going to be perfect for 70 minutes - as much as I hope it one day might be - and I what it comes down to is personal qualities.
"When it became 3-3 I thought 'fair play to them'. They got on the front foot, got into the circle and converted two opportunities very well.
"In terms of those qualities you look for from a high-performing team I was absolutely delighted. It is the Olympic Games and you have performances like that but it is how you come out of them that is the thing.
"When the pressure came on they did what they did. It would've been easy to go on the back foot and let Korea roll us over and we didn't and I am delighted for the girls."
With captain Kate Walsh watching on from her hospital bed as she recovers from surgery to have a plate inserted in a broken jaw the last thing GB needed was to see star striker Danson leave the pitch on a stretcher and the ground on crutches. However, her injury was assessed as only a rolled ankle and not deemed serious.
One problem Kerry has discovered, however, is that the noise of the 16,000-capacity stadium makes it almost impossible for the coaching staff to communicate with players on the field. "It is an issue we've never had before," he added.