Michael Jolley praised the homework done by his goalkeeping team after Grimsby booked a trip to Chelsea in the Carabao Cup.
After the rearranged second round tie against Macclesfield finished goalless, goalkeeper James McKeown produced two decisive saves in a tense penalty shoot-out.
He denied Fraser Horsfall and Connor Kirby from 12 yards as Grimsby won the battle of Sky Bet League Two sides at Blundell Park.
Jolley’s men will now head to Stamford Bridge on Wednesday, September 25 – and the trip is down to more than just one man.
“Fair play to (goalkeeper coach) Sam Russell as well,” said Jolley.
“Macclesfield have been involved in a few penalty shoot-outs. Sam did a lot of homework on their penalty takers and Macca (James McKeown) executed it really well.
“He’s already a legend here and I’m sure those saves just add to that status more.”
On progressing through to face Premier League Chelsea, Jolley added: “What I need to say is that (Macclesfield manager) Daryl McMahon and his team showed a lot of class – during and after the game.
“They wished us well and wished us luck for the game at Chelsea.
“It’s difficult to do that when you’ve just lost the game. I have a huge amount of respect for Daryl and his team, for that moment and the way they play the game.
“Penalty shoot-outs are a 50-50 situation. I think our players held their nerve really well and, obviously, our goalkeeper made two fantastic saves.
“Well done to all the players. They have got a big date in the diary to look forward to.”
Clear-cut chances were at a premium in the opening 45 minutes, with McKeown only called into action to make routine saves from Theo Archibald and Kirby.
At the other end, after the restart, forward Moses Ogbu saw a goal-bound effort cleared off the line, while James Hanson passed up the sort of headed chance he usually buries.
Matt Green and Max Wright also went close for the home side, who ultimately progressed courtesy of McKeown’s heroics.
He guessed right on two occasions as the shoot-out finished 5-4 in Grimsby’s favour.