Colin's Sister continued her winning spree with a comprehensive success in the Weatherbys GSB Goes Online Jane Seymour Mares' Novices' Hurdle at Sandown.
Placed in a Listed bumper at this venue last spring, the Fergal O'Brien-trained six-year-old made a winning start to her career over jumps at Chepstow in October before bolting up at Warwick.
She comfortably graduated to Listed class when completing her hat-trick at Haydock and was the even-money favourite stepped up to Grade Two level in Esher.
Paddy Brennan's mount was never too far off the speed and tracked the pacesetting Happy Diva into the home straight.
Brennan looked behind for non-existent dangers on the run to the second flight from the finish and a bold leap saw her land in front.
Colin's Sister quickly put daylight between herself and her toiling rivals and while she hung under pressure on the long run-in, she still passed the post with nine lengths in hand.
Happy Diva clung on to second place from Ms Parfois.
O'Brien said: "That was very good and we were very hopeful coming here today.
"She is a racehorse and a filly and sometimes it's not always straightforward, but she is pretty straightforward and pretty special and we're lucky to have her.
"Paddy was happy with her. He gave her a squeeze going down the hill and she was on and off the bridle a bit, but she's given some nice fillies 5lb and annihilated them."
Colin's Sister could step out of novice company for a shot at the OLBG Mares' Hurdle at next month's Cheltenham Festival, with O'Brien not keen on dropping in distance for the Trull House Stud Mares' Novices' Hurdle at the showpiece fixture.
He added: "We'll get her back and speak to Paddy. Do I go for the Mares' Hurdle, or keep to novice company as we have done all season?
"The mares' novice hurdle would be too short, unless it came up very soft. My heart is saying the David Nicholson, as that's the one we all want to win, but there's some very good mares in it. The Albert Bartlett could be another option.
"It might depend on the ground. Ideally she wants it soft, but even she found it hard work today."
There was a shock result to the Telegraph Hill Novices' Hurdle, with 9-1 shot Gregarious seeing off 1-7 favourite Percy Street.
The Nicky Henderson-trained Percy Street was sent off at extremely prohibitive odds to follow up his victory at Taunton three weeks ago and tracked Gregarious into the home straight.
Nico de Boinville was soon at work aboard the market leader, however, and he ultimately came up well short, with Lucy Wadham's charge coming home with nine lengths in hand.
Wadham's husband Justin said: "His first run as a two-year-old was very good but he has slightly lost his way since. He has always had ability, it has just been a question of whether he would settle.
"He is learning to settle with each race. He was mad fresh at Wetherby and better at Plumpton and today he was more professional. He is a strapping horse and will make a nice two-mile chaser.
"I don't know whether the other horse (Percy Street) ran to its mark and our one had the race to suit him. We assumed we would be looking a lowly handicaps, but after this it might be something a bit less lowly now."
Chieftain's Choice (3-1) ended trainer Kevin Frost's 52-day barren run when gaining his first victory since December 2014 with a length-and-a-quarter success in the two-mile conditional jockeys' handicap hurdle, to give the Shropshire trainer his first winner at the track.
Frost's wife Amanda said: "The previous owner wanted to ride him from the front, but Kevin said he needs to come from the back and he has proved that.
"You just have to be brave on him, as once he hits the front he stops. This is good for a little yard like us and it makes the journey worthwhile."
Speredek (7-1) could be in line for a quick reappearance after backing up his recent success at Taunton with a front-running victory in the 'Ubique' Handicap Chase.
Trainer Nigel Hawke said: "The race at Market Rasen on Sunday reopened and if something happened early today we had that as a second option, but don't rule anything out.
"He is a classic two-mile chaser, though he might get two and a half. He loves jumping and galloping and those horses are worth their weight in gold."
The first-time visor worked the trick on the Alan King-trained Willoughby Hedge (8-1) after he opened his account for the campaign in taking the three-mile handicap chase by two lengths.
Assistant trainer Dan Horsford said: "The visor obviously woke him up a bit. He jumps so well and Wayne Hutchinson said he got into a nice rhythm. This time last year we were looking at Cheltenham with him, but he went wrong before that."
Justification (5-1) put his injury problems behind him when taking the concluding two-and-a-half-mile handicap hurdle for trainer Gary Moore by six lengths.