Monaghan had to rely on all their big game experience to see off Cavan by the narrowest of margins, 0-16 to 0-15 at Breffni Park on Sunday.
“At half-time we were in a good enough position playing with the wind,” said Monaghan boss Malachy O’Rourke.
“Cavan came out in the second half and started very well. There was a stage when if the boys had not held their heads we could have been a number of points in arrears and it would have been difficult to come back.
“I thought we controlled things a bit better in the second half and got Conor on the ball a bit more and we are delighted to get the win.”
Five points in a ten minute spell midway through the second half nudged Monaghan ahead and although Martin Dunne equalised for Cavan with four minutes remaining, a superb score from Conor McManus helped get the visitors over the line.
The sides were level five times in a gripping first half, after which Cavan led by 0-9 to 0-7 having had the wind.
The winners will now face either Fermanagh or Antrim in four weeks’ time for a place in this year’s provincial decider.
“We went out and we battled hard and worked hard but we just came up short,” said Cavan boss Terry Hyland.
“You have to be proud of our honesty and workrate but for a little more finesse on the ball and not taking the ball into a tackle - there was only small margins in swinging it around.
“We knew it was going to be tough in the second half because we had been playing with a fair breeze.
“We felt was a benefit to us in the first half and that maybe we should have been a bit further ahead at the break. We asked the lads to put up a strong second half performance which we did but we came up short,”
Cavan minors had a comfortable victory over Monaghan to book their place in the Ulster MFC semi-finals.
A strong 20-minute spell before half-time, when they outscored Monaghan by 2-5 to 0-4 proved decisive.