Pukki, from the penalty spot, proved the matchwinner against Bournemouth on Saturday.
"It's huge. We have played really well lately but have not been able to take the three points. It was important for the team and for the confidence. There is still a long way to go, but we are ready to fight," Pukki said.
"We had a hard time getting three points against the other bottom teams, so it was important today.
"We still believe in ourselves, though there are not others who do."