The reigning champions fell to a 19-14 defeat to the Ospreys at the Liberty Stadium on Saturday night - their fourth loss in five Magners League games on the road.
McGahan's men have now been beaten at Glasgow, Leinster, Edinburgh and the Ospreys so far in 2009/10.
That is in stark comparison to last season's title-winning campaign when Munster only suffered three away defeats all season. The fact that those defeats came at venues that Munster are yet to visit this term (Ulster, Connacht and Cardiff Blues), makes the current slump in away form even more worrying for the red faithful.
"Our away form hasn't been good at all," said McGahan.
"Looking at last year's results that we had against Glasgow and Edinburgh and also the corresponding fixture here (at the Ospreys) which we won, we're already down nine points in terms of what we accumulated last year.
"Our consistency away from home is definitely a real concern."
Munster led 7-6 at half-time at the Liberty Stadium in Swansea before a Tommy Bowe try and a further eight points from the boot of Dan Biggar saw the Ospreys pull clear after the break.
And McGahan was understandably disappointed with his side's second-half performance after a bright start to the match had suggested an away win may well have been on the cards for the first time since September's narrow triumph at the Scarlets.
"It wasn't a great game to be honest. There wasn't much flowing play from either side and there was a lot of kicking," added McGahan.
"In the first half we competed well enough, we had good field position but unfortunately came up short with a few kicks which could have led to a larger scoreline at half-time.
"But our discipline was poor in the second half and we gave away crucial penalties which could well have been avoided. Having two men in the bin for 20 minutes makes it very difficult to compete against a good side like the Ospreys."
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