Whelpdale was surprisingly picked at right-back against Bristol City at the weekend and is expected to line up for the Posh again, before the side face home clashes against Scunthorpe and Barnsley.
"We definitely need to get the three points at Doncaster and the same applies to the two home games as well," he told the Evening Telegraph.
"There is no such thing as an easy game at this level, but they are the sort of matches we all believe we can.
"Everyone is capable of beating everyone else so any team that can
get on a little run will make a lot of progress in the table.
"We have proved we are capable of doing just that in the previous two seasons and hopefully we can put some results together again."