Put into bat, Louth openers Scott and Cartledge started well before the latter fell for nine.
When Scott went after a well-made 40, Louth were 48-2.
Louth overseas player O'Donohue and Collinson then put together a 89 partnership to take Louth to 137 before Collinson (44) went.
A determined Scunthorpe side then took four quick wickets for 19 runs leaving Louth 169-7 and in danger of falling well short of their targeted score.
But How Tye (24) and McLoughlin (31 off 23 balls) batted exceptionally and smartly taking Louth onto a final score of 226, putting on a vital 57 in nine overs.
Louth set out defending this total with Koen (1-34) and Collinson (2-33) bowling tight, Koen making an early breakthrough, dismissing Mann with a short ball.
Scunthorpe's Australian Evans batted well bringing up his 50, keeping their hope alive and Louth knowing his wicket was key.
Young James Mason (2-50) changed the game in Louth's favour with an smart reflex caught and bowled to dismiss Evans (61).
Collinson then took two wickets in two balls to leave Scunthorpe on 104-8 off 31.
Momentum changed again with Brumby keeping the scoring going and creating a hard last 15 overs for Louth to restrict them with a bowler down due to injury to McLoughlin in the field.
Another young Louth player, Oliver Shufflebotham on his debut impressed by bowling tight while under pressure.
Scott came on to see the innings out from one end and Mason returned from the other.
Bowling under pressure as Brumby made 78 not out, they saw Louth home with Scunthorpe eventually falling short on 201-8.
Player of the Match was Henry Tye for 3-33 and an important quick 24.
Louth travel to Market Rasen for a cup quarter-final this weekend.
Louth seconds suffered a resounding loss to top of the table Lindum, with a much depleted side. However, debutants Joshua Brindle and Henry Househam impressed massively and returned from the third team to the side this week, as Louth faced Outcasts.
On winning the toss and deciding to chase, Louth's opening bowlers of Brindle and Billings showed great discipline to restrict Outcasts to only 25 off the first 11 overs.
This theme continued as Louth's change bowlers of Stewart West, Fergus Ringland and Shazaib Ansar all bowled very tightly.
This pressure allowed Sachin West to take a three wicket haul with his leg spin, whilst Blake Billings returned very tight figures and took two wickets by the close, as Outcasts finished on 159-7.
This target seemed not enough on a good surface and quickening outfield and sure enough with good innings from Stewart West at the top (31), Wayne Garlic (40) and Sachin West (60), Louth looked in total control at 143-2, with 12 overs to spare.
However, when Garlic and Sach West fell in consecutive overs, there was a plethora of wickets and Louth suddenly found themselves trying to snatch defeat from the jaws of victory at 148 -7.
But the cool heads of Toby Precious and Shazaib Ansar took Louth over the line to a fine victory. Real praise goes to all the junior contingent yet again, especially Henry Househam with his expert cover fielding.
Player of the match went to Sachin West for 3-36 off eight overs and a match-winning 60 with the bat.