The Scottish ace clinched the women's title in style on her PortsmouthÂ bow.
McColgan delivered a barnstorming performance to stop to clock on 54mins 43secs, replicating the success of her mum, Liz, who claimed the race in 1995 and 1997.Â
McColgan satÂ just offÂ long-time leader Steph Twell before pulling clear around the eight-mile marker.Â
Twell finished second with a time of 55.16, while last year's ladies' winnerÂ Gemma Steel (56.56) completedÂ the podium places.Â
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McColgan's debut alongside Southsea seafront was the first time she stepped up to the 10-mile distance.
Having raced at shorter trips '“Â and on the track '“ for most of her career, the 27-year-oldÂ she wasn't sure how she would fare.
McColgan admitted she was surprised she felt so comfortable in the latter stages of the affair.
And the 2012 and 2016 Olympian surpassed her own expectations by claiming the title.Â
McColgan said: '˜I'm over the moon with the win.Â
'˜Not having raced over 10 miles probably helped me a little bit.
'˜I didn't have to think about what it was going to be like because I didn't know what it was going to be like.
'˜The pace at the start was quite comfortable and suited me. Before the end I had a lot more in the legs than I initially thought.
'˜At eight miles I felt really strong and when I saw there was a mile to go I knew I was entering my territory as it's where I do well on the track.
'˜I knew if I could be there with a mile to go I'd have a chance of winning '“Â but the main thing for me was being there at nine miles!
'˜I got to 10km and mentally for me that was the toughest part but when IÂ pushed on I was comfortable.Â
'˜It was certainly more than I imagined happening.
'˜I was a little bit scared because with two miles to go when I hit the frontÂ I was thinking 'what do I do here?'
'˜I wasn't sure to stay there or to try to sit back and slow the pace down.
'˜I certainly didn't expect to find myself there with two miles to go.
'˜At that point I threw caution to the wind and didÂ everything I could.
I could almost sense there was an opportunity to win, which helped spur me on.
'˜Leading into the last mile, I thought 'I can't lose it now' after getting that far and I'm really, really happy.'