Portadown survived growing second-half pressure to leave The Oval on Saturday with a league point from the Irish Cup final dress rehearsal.
The scoreless draw against Glentoran was played out in strong winds that restricted the chance for passing football - despite high stakes with both sides pushing for European qualification.
The Ports enjoyed a short early spell on top, with Shea Conaty unable to gain a clean connection on Sean Mackle’s looping cross after a sweeping pass out wide by Peter McMahon.
Teenager Jordan Lyttle - so impressive in the previous fixture against Crusaders - replaced the injured Ken Oman with six minutes on the clock and produced another assured display at centre-back.
Lyttle was on hand with a sliding block to clear the danger a few yards in front of the exposed net off Danny McKee’s shot.
Portadown squandered a golden opportunity to break the deadlock on 35 minutes when McMahon’s clever turn and cross was controlled by Gary Twigg but Elliott Morris blocked the shot with his legs.
Twigg collected a pass from deep by Darren Murray early in the second half. However, with two defenders blocking his path to goal, the striker opted for a shot from distance that cleared the bar.
Glentoran had the upper hand after the break but Portadown managed to protect the clean sheet.
The impressive Billy Brennan pulled off an acrobatic and inventive save to deny McKee with a crucial forearm touch that diverted away the close-range flick.
Moments later he raced out with a brave block to frustrate David Scullion.
Kym Nelson flashed an angled long-range drive past the post as Glentoran pushed hard.
Another superb chance arrived for Twigg at the back post but he hit the upright off Chris Casement’s teasing low cross, following a well-worked passing move involving McMahon and Robert Garrett.
PORTADOWN: Billy Brennan, Chris Casement, Ross Redman, Keith O’Hara, Peter McMahon, Tim Mouncey, Sean Mackle, Ken Oman, Gary Twigg, Shea Conaty, Robert Garrett. Subs: David Miskelly, Darren Murray (on for Conaty, 39 mins), Jake Richardson, Marcio Soares, Jordan Lyttle (on for Oman, 6 mins).