Giving weight all round, the six-year-old looked beaten halfway up the straight as Lady Buttons joined her but, come the line, champion jockey Richard Johnson had forced her two lengths back in front.
Greatrex said of the 10-11 favourite: "She's tough. Richard said they hadn't gone quick so he was keen to press on a long way out as she doesn't have a turn of foot."
The trainer added: "She's built like a chaser so we need to decide whether to go chasing or stay over hurdles as there are so many nice prizes for these mares now.
"She still hasn't quite got to where I thought she would."
Kalashnikov (4-1) maintained his unbeaten record with a stylish performance in the bet365 Novices' Hurdle.
Winner of a bumper at the track in March, the eyecatching four-year-old was a 10-length winner under Jack Quinlan.
Having cruised to the front, he then looked a sitting duck at the second-last as Harry Skelton loomed large on 6-4 favourite Al Shahir but he had no answer to the impressive winner.
"He's a very nice horse, we've always liked him," said trainer Amy Murphy.
"He'll want further in time but the turn of foot he showed there we'll stick at two miles for now and go somewhere under a penalty."
The two-mile novice chase was won in fine style by Dan Skelton's Born Survivor (4-6 favourite), who never touched a twig on the way round.
"He was in the process of running a big race in the Morebattle last year when he fell," said Skelton.
"He's always promised a lot. I think we'll stay at two miles until he gets beaten."
The opening three-mile handicap chase was won in effortless fashion by David Pipe's Daklondike (5-1) for Tom Scudamore.
"It's a good job I entered him for Hexham on Friday as he might be getting a bit of a hike in the weights," Pipe said of the 18-length winner.
"We've had a few winners this week and this is traditionally when our better horses come out."