The Dragons led for large spells of Saturday's encounter at Rodney Parade and when Tomas O'Leary was sent to the sin-bin in the 58th minute, the champions were wobbling.
But despite missing 20 players through international commitments and injuries, Munster rallied superbly with tries from Luke O'Dea and an interception effort from Felix Jones to make it four straight wins in the RaboDirect PRO12 since the turn of the year.
And while the scoreline was not as emphatic as some of their previous results, McGahan was far more delighted with a backs-against-the-wall performance that showcased the champions' credentials.
"It is a real testament to the group and to their character for what they showed in this one," he told the Irish Times.
"It is a very difficult place to play for every team that comes here. To get away with the result certainly puts us in a great position. The players are working extremely hard during this period and it shows.
"We left a lot out there but we knew it would take that. Certain parts of our game malfunctioned.
"We fell back on our defence this evening and the way that we defended, the way we worked really hard on the ball, certainly gave us great opportunity to withstand some spirited Dragons attack.
"If you really want to be a force in the competition and looking for a home semi-final you need to be winning on the road and certainly for us we are very pleased with this win."
63x46.png){kind=logo}