We head to the South Coast in the Premiership on Wednesday and then return on Saturday in the third round of the FA Cup.
Les is unavailable for the games due to suspension, but feels the boys are in good enough shape to succeed on the tricky mission.
"It will be a tough game on Wednesday, but I think they've got to take heart from some of the performances they've put in of late.
"We've shown a determination and ability to perform well, score goals and we've got to get back to that again.
"We must put Newcastle behind us because I don't think we played badly there. The team did well and it was just unfortunate we didn't put our chances away.
"What we've got to do is move on from there and start another run."
Les Ferdinand insists the team should take heart from the quality of recent performances as they prepare to tackle Southampton in part one of the St Mary's double-header.