Murdoch led a 349-strong field home in a time of 17:50 - just a second ahead of fellow veteran male 44-45 category runner Sam Taylor-Allkins.
Teenager Thomas Beasley, who was third in the Havant parkrun the previous day, was third in 18:06.
City of Portsmouth AC member Corin Bearpark was the first female to finish in the 349-strong field, clocking 20:34 for 22nd place.
Denmead Striders’ Julian Manning was easily first home in the opening Great Salterns parkrun of 2023.
His time of 18:45 was well clear of runner-up Emma Jolley, the City of Portsmouth AC runner recording 20.29. Mark Bicknell (Denmead, 20:40) completed the top three.
A Denmead member was also first to finish at the New Year’s Day Havant parkrun, Richard Murphy clocking 18:38 - well ahead of Jack Audrin (20:21).
Victory AC’s Jo Stanford was the first woman to finish at Staunton Country Park - for the second day in a row - in 22:25 (seventh place).
Teenager Harry Harvey led a 374-strong field home at Lee-on-the-Solent.
The Winchester & District AC member recorded a time of 17:34 - almost a minute quicker than Tommy Blake (Loughborough Triathlon) in 18:32.
James Lee (Fareham RC) was third in 18:53, while Nikki Moxham (Gosport Road Runners, 19:46) was first woman to finish (12th).
Oli Hawkins was a clear winner of the first Fareham parkrun of 2023.
The New Forest Juniors AC member clocked 18:40 - 62 seconds ahead of Fareham RC’s Samuel Brooks.
Helen Knight, on her first visit to the Cams Hall Estate course, completed the top three in 20:34.
13. New Year's Day parkrun, Southsea. Photograph by Sam Stephenson
New Year's Day parkrun, Southsea. Photograph by Sam Stephenson Photo: -