Town's 3-0 home defeat to promotion-chasing Bournemouth on Saturday, combined with results elsewhere, leaves the 18th-placed Shrews six points clear of fourth-bottom Scunthorpe, who have nine left to play for.
Financially-stricken Bury have already been relegated with Hartlepool and Portsmouth also both on the brink and unable to catch Town.
Scunthorpe would see their hopes of overtaking Shrewsbury all but disappear if they lose their game in hand at Gigg Lane on Tuesday night, but Turner is focusing on matters closer to home and Town's remaining games against three relegation rivals in Colchester, Oldham and Portsmouth.
"We've got three massive games left and we need one win," Turner said. "We have to regroup. It's no good getting carried away because of Saturday's defeat."
He added: "I doesn't surprise me that Oldham won at Bury on Saturday, Bury sound as though they've got real problems there. That result didn't surprise anybody.
"The Colchester one went okay for us, losing at Notts County, Scunthorpe are up by a point.
"We're six points ahead of them with a better goal difference, we've got three big games now and three games we're capable to taking something from. I've got no doubts in my mind that we'll do that."