Trump has already won this season to climb to near the top of Class Three but the big chestnut showed with a strong trial on Tuesday that he may still have some more ratings points in hand.
It took a season of acclimatising and a considerable drop in the handicaps for Trump to become competitive this season, with Manfred Man Ka-leung's five-year-old finally breaking through over a mile at Sha Tin off a rating of 78 - a mark he has remained at with three decent efforts with big weights.
Man may even consider a start on the all-weather track after the son of Written Tycoon towed Douglas Whyte through a strong 1,200m effort.
Trump went slow early but gradually built up steam throughout and when challenged by Zaidan he found another gear while still under a hold by Whyte.
While the overall time of 1.12.6s wasn't exceptional, a final 400m split of 21.6s and the way Trump ran through the line was.
Zaidan was under hard riding by Matthew Chadwick as trainer Tony Cruz prepares the 2012 Hong Kong Classic Cup winner for a trip to Macau for the second leg of the interport series, the Macau Hong Kong Trophy, on May 31.
In the second heat, even though he missed the start, Cruz's three-year-old New Zealand maiden winner Clever Beaver made a good impression in his first local trial.
The 66-rater cruised to win his heat in a time half a second faster than Trump's, after showing some maturity to sit behind leader Splendid Days (Whyte) and then kick after pushing out from his trailing position in the final 200m.
Clever Beaver actually won his Ellerslie maiden on protest, crossing the line half a length behind the first horse across the line before the result was overturned by stewards because of interference.
