In the old days, a goal was 3 points, a penalty was 3 points, and a try was 5 points. That's seventeen- unless the goal was a conversion, which was two points, and the total becomes sixteen. And if the try was converted (and not mentioned) that makes nineteen.

"One goal, three penalties and a try" has echoes of Tom Lehrer's "three game wardens, seven hunters and a cow".