After wiping out a 20 point deficit to lead 27-26 against Benetton it looked as the deserved away win would come.
As the clock turned red, retaining the ball from a scrum would allow the visitors to to kick it off the park to secure victory at Stadio di Monigo.
But a collapsed scrum resulted in a penalty for the hosts even though he had warned the Benetton Rugby tight-head three times in earlier scrums.
Of the 26 players that are currently in Italy for the Dragons, nine have made their debuts this season while two others, lock Joe Davies and fly-half Arwel Robson, had only previously been involved in the Anglo-Welsh Cup.
"Even though we lost, it was still a step forward for us," said Jackman after the game. "The performances of players like Arwel Robson, Connor Edwards, Jared Rosser and Taine Basham when he came on were really encouraging. We are building for the future with our younger players.
“They reckon it takes eight to 10 games before players get comfortable playing at this level and that’s why we are trying to give our youngsters that game time this season in readiness for our next campaign.
“Even though the result was a negative, when we started to play in the second half we looked really good.”
