Maguire scored a hat-trick for Cork City in their 4-2 victory over Levadia Tallinn in the Europa League on Thursday night.
His treble helped Cork to a 6-2 aggregate win against the Estonian side in the first qualifying round clash.
Maguire and City team-mate Kevin O'Connor agreed moves to North End last month and will join Neil's squad on July 24.
After Maguire's hat-trick, Cork manager John Calufield said: "Sean is just so determined and so focused.
"Another man could have switched off after getting his move and not kicked a ball.
"He has been incredible and that is why I think he will be phenomenal for Preston.
"In some ways a brand new manager coming in there might actually suit him.
"He goes there in tip-top form while their team has only just started pre-season training.
"Sean goes over there after six months of scoring goals week in, week out.
"That could be a major benefit to him, likewise Kevin O'Connor."
Maguire and O'Connor will next be in action for Cork on Sunday in a League of Ireland clash with St Patrick's Athletic at Turner's Cross.
North End won't be far away, with them training at Fota Island next week.