The handicapper holds the key to the chances of Saturday's brilliant Prime Minister's Cup winner Famous Seamus's winning the Group One Stradbroke Hcp (1400m) next month.

Famous Seamus ($7) scored by a neck to River Lad ($11) with a half neck to Fire Up Fifi ($10) in Saturday's 1300m Listed race.

Trainer Noel Mayfield Smith is convinced Famous Seamus can emulate his 2000 Stradbroke winner Landsighting who won the Group One race with only 49kg.

"Famous Seamus is not as mature as Landsighting but he can run similar times on the track. But I am starting to worry about the handicaps for the Stradbroke," he said.

Famous Seamus humped 57kg to win Saturday's race which will impact on his Stradbroke weight which will be released later this month.

The four-year-old won the Listed Hinkley Quality with 56kg at Eagle Farm last month after weights were raised two kilos.

"It in effect meant he was penalised three kilograms in this race today," Mayfield-Smith said.

Famous Seamus will probably have his next start in the BRC Sprint at Doomben on May 25.

However, Mayfield-Smith is also considering a barrier trial instead of a race.

"He has done very well up here and in fact he has done a lot better than when in Melbourne last year," he said.

Winning jockey Glen Colless said Famous Seamus had enjoyed a perfect run behind the pace before getting clear in the straight.

"He showed a lot of fight when they came at him in the final 100m," he said.

Eddie Wilkinson said his mount River Lad had not enjoyed the same luck as the winner.

"Reverse the runs and it might be different," he said.

River Lad's trainer Natalie McCall said the gelding would have his next start in the BRC Sprint.

Ryan Wiggins rode Fire Up Fifi on Saturday and said she had passed her toughest assignment to date with aplomb.

"She is ready to take on better races," Wiggins said.

Mahisara was backed from $8 into $5.50 favouritism and finished fourth with his jockey Jim Cassidy saying he had to work too hard to get to the lead.