Simonsen, 32 has been virtually ever present in the Blades 2011/12 League One promotion chasing season so far - with the exception of a mini run of games handed out to George Long last October. In his last four appearances Simonsen has kept two clean sheets in victories over Yerovil Town (4-0) and Bury (3-0).
Simonsen said: "It's all down to the lads in front of me. To be honest I've not had an awful lot to do.
"What I've had to do I've managed to do it, but I've not been over-worked and that's all credit to the lads in front of me, the back four, the midfield and also the lads up front because we defend from the front.
"That's where defence starts for us and we've done it really well, we've kept teams out."