Margretta, who won by 10 lengths, had won a maiden race at Riccarton at her previous start.
She is raced by Hamilton and Peter Lyon, of Alexandra.
The rising 6yr-old Pentire mare had her first start for Hamilton in January after four unplaced runs in the North Island.
Laudercreek cleared maiden ranks after placings in two of his three starts.
He is raced by Hamilton in partnership and trained by Ben and Sally Gordon.
Laudercreek is among 21 horses the Invercargill trainers have based at Riccarton for winter racing.
The rising 4yr-old Laudercreek is co-owned by Ben Gordon and Brian Bruce and Terry Stewart, of Alexandra.
Bruce owned and trained Random Choice to win the 1995 Hazlett Stakes.
Hamilton secured Laudercreek as a youngster from Stoney Bridge stud, Matamata.
He passed the gelding to the Gordons to iron out his barrier manners.
The group was then formed to race the gelding.
Laudercreek is by Storm Creek out of Heinie Hartwig, a half-sister by Chem to Narousa, whose 11 wins included the 2001 Dunedin Cup.
New Zealand Grand National Hurdles, Great Northern and Waikato Hurdles and Kumara Nuggets.
The Gordons have Bonbonniere, Le Thunder and Aristrocrat ready to resume racing.
Le Thunder won the Amberley Cup last year when trained by Michael Pitman. The Le Paillard gelding has not raced since finishing fifth in the Winter Classic at Riccarton last August.
He did his early racing from the Gordon stable.
Aristocrat, twice a winner from 12 starts, was sidelined with a curbed hock.
He has not raced since May last year.
Bonbonniere was spelled in April.
She has won over 2000m at Gore and Ascot Park this year.
Chris Johnson won the Amberley Cup for the third time as a jockey at Riccarton on Saturday.
His trio of winners have been trained on the track.
Johnson rode Romany, trained by Laurie Jarvis, his owner-breeder.
Johnson has also won the Amberley Cup on Mitchell Sage (1989) and Paddy Speed (1983) when the race was over 2100m.
The race was over 1200m on Saturday.
Paddy Speed was trained by Garth Jackson and Mitchell Sage by Peter and Dawn Williams.
Johnson was suspended for six riding days from next Monday until midnight on July 15 for careless riding on Romany.
He admitted shifting out at the 500m, causing a severe check to Kimberley Boy.
Zman Zukifli was fined $200 for failing to ride out Albufeira, who finished sixth.
Trainer John Phillips told stewards that he considered Doeface had choked when finishing a distant last.
He found dirt in the mouth of the horse after the race.
The riders of The Jackal, Minnaloushka, The Debt Collector and John Cash advised stewards that their mounts did not handle the heavy track.
