And a win this week, following last month’s 34-26 success, would end the Stags’ 2014 campaign.
Thunder coach Stanley Gene has no new injury worries, with his side’s last game coming 11 days ago with a 40-14 win over Oldham.
But Stags coach Troy Perkins will be without four players due to Sunday’s scheduled kick-off time of 6pm.
Perkins said: “I’ve got three or four players that won’t be able to make the trip due to work commitments first thing Monday morning in London.”
But Perkins remains upbeat, adding: “We’ve got results in our last two games to get us in the play-offs.
“We know Gateshead well. We’ve played them three times, and there hasn’t been much between us in the three games we’ve played.
“They’re a dangerous team who are good in attack, with two smart halves, and they’re hitting some form too.
“They’ve won against some top teams recently, and they were impressive against Oldham.
“But we’ve worked really hard on our defence, and we’ve got to be good there to give ourselves a chance.”