In the following year, she was beaten over a mile in the classic 1000 Guineas but returned to sprinting to win the King's Stand Stakes July Cup and Prix de l'Abbaye.
Marwell was a bay filly with no white markings bred by her owner, Edmund Loder, at the family's Eyresfield Stud near the Curragh in County Kildare.
[7] With Piggott serving a suspension, Greville Starkey took the ride on Marwell when the filly was matched against colts in the Group Two Flying Childers Stakes at Doncaster Racecourse in September.
She was made the 4/11 favourite[6] and after starting slowly took the lead approaching the final furlong and drew clear of her opponents to win by three lengths despite being eased down in the closing stages.
On her final appearance of the season, Marwell contested the Cheveley Park Stakes, then the only Group One race in the United Kingdom restricted to two-year-old fillies.
[9] In June, Marwell was matched against colts and older horses at Royal Ascot in the King's Stand Stakes, one of three Group One, all-aged sprints run in Europe at that time.
Swinburn had to attend a disciplinary hearing at the Jockey Club on the morning of the race but had a car standing by and reached Newmarket in time to ride the filly.
[12] At Haydock in September, Marwell sustained another upset defeat in the Vernons Sprint Cup when she was narrowly beaten by Runnett, a four-year-old who had finished third in the King's Stand Stakes.
She produced at least eight individual winners, including two who succeeded at Group One level: Marwell was retired from stud duties in 2002 at the age of 24[21] and was euthanised at Eyresfield in the following October.