While Rs have struggled to pull away from the bottom of the table, Southampton put enough wins together to move clear of the drop zone ahead of the clash at St Mary's.
Townsend, on-loan from Tottenham, told the Fulham Chronicle: "From now until May we have a lot of six-pointers against teams we are trying to catch, like Southampton, Sunderland, [Aston] Villa and Wigan.
"It is a massive two or three months, but it's quite simple what we have to do, and that's beat those teams around us. That's what will shape our season - it's in our own hands then.
"We need to do what Southampton did and pull away, but it's not just them - we have to look at what teams like Swansea and Norwich have done since coming up for inspiration.
"We have the quality, we just need to go on a good run of our own. We're well overdue one as we've not had one all season really."