Glenavon had first-half goals to thank for derby delight as the Lurgan Blues survived a red card for James Singleton after the break and Portadown penalty to secure success by 2-1.
Glenavon arrived at Shamrock Park bolstered by one signing - Brazil-born Renato Devicchi Martins from Thisted in Denmark - and speculation over a pre-contract agreement for Andrew Mitchell to arrive this summer from Dungannon Swifts.
However, the Lurgan Blues’ frontline of James Gray and Greg Moorhouse offered evidence of firepower already in place by each finding the net ahead of the interval.
Gray broke the deadlock on his first league start for Glenavon by slotting in a close-range shot off Moorhouse’s pass across the box as Portadown had appeals for offside dismissed by the match officials.
It was 2-0 thanks to Moorhouse as the striker turned from provider to scorer by capping a near-post run with a slick strike to convert Joel Cooper’s cross, after initial positive play by Gray.
Portadown, who announced the arrival of former Glentoran player Philip Carson prior to kick-off, offered a response in stages as Adam Foley looked sharp.
Shea McGerrigan forced Jonny Tuffey into a near-post save off his sidefoot volley late in the first half.
The game’s second half sparked into life after 51 minutes when James Singleton was sent off for a foul on Foley in the box and Niall Henderson converted from the penalty spot.
However, Portadown pressure failed to result in an equaliser and Rhys Marshall came close to increasing the visitors’ lead with a run from one box to another that ended with the full-back firing against the crossbar.
PORTADOWN: Chris McGaughey, Brendan Shannon, Matthew Parker, Alan Byrne, Jordan Lyttle, Niall Henderson, Zac Wilson, Adam Foley, Aaron Haire, Tiarnan Mulvenna, Shea McGerrigan. Subs: Conor Larkin, Marcio Soares (Haire, 86), Jaime Gardiner (Henderson, 93), Callum Ferris (Mulvenna, 75), Tim Mouncey.
GLENAVON: Jonny Tuffey, Simon Kelly, Andy Kilmartin, Rhys Marshall, Joel Cooper, Mark Sykes, Caolan Marron, Greg Moorhouse, James Singleton, James Gray. Subs: Gary Hamilton (Gray, 81), Aaron Canning (Kilmartin, 38), Mark Patton, Andy McGrory, Guy Bates.
Referee: Ian McNabb.