The on-form forward was at it again as the Saints took National League South leaders Dartford apart at Clarence Park.
The stunning 4-0 win came seven days after Allinson’s team ripped East Thurrock to pieces, 7-2 it finished in Hertfordshire.
Merson scored four that afternoon and seven days on - and with a new contract signed - things are looking very promising for the son of former Arsenal and England star Paul.
The game was a feature match this afternoon and St Albans’ boss told the National League’s Oli Osborn: “When Sam is on fire, which at the moment he is, there really isn’t many better in Non-League football.
“Sometimes he plays and you think ‘come on, give me a little bit more’ but today has scored two great headers, he isn’t the tallest but he knows how to score them.
“The great news is that he has just signed a two-and-half year contract with us. So here’s our player - and if anyone wants to sign him, they are going to have to pay some good money!
“He needs that chance to play in the Football League. When he gets inside the box he comes alive.”
Allison was thrilled as his team produced arguably the shock result of the season.
“We continued from what we did last week against East Thurrock United,” he said.
“The first 35 minutes was a fantastic game to be apart of. It was so end to end and any team could have gone in front.
“But we managed to nick two goals just before half time and I think that actually changed the game.
“We scored at important times - even the third and the fourth goals arrived when we needed them to.