The highlight for the home fans was a double strike from striker Gary Twigg as Ronnie McFall's side showed they will be a force to be reckoned with this season.
Johnny Tuffey made the first of two crucial saves when he turned away a long range Chris Casement free kick on four minutes.
The Linfield keeper did even better six minutes later with a point blank save to deny Gary Twigg, who got on the end of a cross from Mark McAllister.
The former Linfield striker was next to go close, after putting the ball through the legs of Jamie Richards he fired a left foot shot straight at a relieved Tuffey.
At the other end Aaron Burns headed just over the bar after neat build-up involving Stephen Lowry and Jamie Mulgrew.
Ronnie McFall's side finally got the goal their early work deserved when Gary Twigg fired them in front on 33 minutes. He was given too much space and made the Blues pay with a superb left footed drive into corner of the net.
Things went from bad to worse for Warren Feeny's side early in the second half when the Ports doubled their lead. It was Twigg again the man on target on 56 minutes when he latched onto a rebound off Hegarty to beat Tuffey.
There was no way back for Linfield on 64 minutes when Ross Redman's low cross was deflected into his own net by Sean Ward to make it 3-0.
Champions Cliftonville had to settle for a point mainly due to some excellent goalkeeping by Elliott Morris in this scoreless draw at Solitude.
The Glens made the better start with Fra Caffrey forcing a fine save out of Conor Devlin on two minutes. The rest of the half was fairly even although Joe Gormley thought he had scored on the stroke of half-time but his effort was ruled out for offside.
The Reds were unfortunate not to score on 48 minutes when Eamonn Seydak picked out Barry Johnston but his firmly struck effort was saved by Morris.
The busy Morris kept the Glens in the game by further saves as he denied Gormley and Chris Curran.
With three minutes left Reds defender Jamie McGovern was sent off after picking up a second yellow.
Cliftonville might have won it right at the death but Morris earned his man of the match award with yet another vital save as he kept out a cross by Curran.
Meanwhile a superb strike from Jordan Owens earned a point for Crusaders as they came from 2-1 down at Mourneview Park in a game which saw a few heated exchanges.
Guy Bates had the first sight of goal on three minutes when he collected a pass from Eoin Bradley but his right foot shot flew inches wide of the post. Kris Lindsay headed home from a Rhys Marshall corner on three minutes but his effort was ruled out for pushing.
Glenavon had a great chance to take the lead on 13 minutes when Bates touched the ball into the patch of Kevin Braniff but his effort went straight to the keeper.
Crusaders, who had been mostly under pressure, went on front on 18 minutes.
A shot from Jordan Owens was cleared off the line by Lindsay, the ball broke to Diarmuid O'Carroll on the edge of the box and his shot went in off the post.
Owens did well to hold off Lindsay to get in a shot but it failed to trouble McGrath as it went wide of the post on 32 minutes. Gary McCutcheon had a chance to double the lead on 32 minutes but his snapshot was saved by the right boot of McGrath.
The Glenavon equaliser arrived on 56 minutes and it had a bit of class about it.
Neill played the ball to Braniff, he cut it in behind the Crues defence and Eoin Bradley flicked the ball over the advancing keeper.
Glenavon took the lead on 71 minutes, Bates heading back into the area and Lindsay with the finish.
That looked like being enough to give Gary Hamilton's side all three points but Owens struck and it was honours even.
A point each, but Ballinamallard left Coleraine Showgrounds the happier of the two sides.
In a game in which both sides struggled to create any real chances of note the draw was perhaps the fair result.
Hegarty has the first effort of the game but he's effort sails over the crossbar. United brought an otherwise poor first half to life on 43 minutes when Jason McCartney found the net.
Coleraine responded with a much better second half and after going close on a couple of occasions they finally got their reward and the equaliser on 83 minutes thanks to a fine effort from David McDaid.
Two goals from David Cushley gave Ballymena United a home win over Warrenpoint Town at The Showgrounds.
United should have scored early on when a corner from Gawley fell to Johnny Taylor but he scooped his shot over the bar.
The ball was soon in the Warrenpoint net and a superb strike it was too from David Cushley who struck a sweet shot into the corner of the net on 15 minutes, the first goal of the new Premier League season.
It was Cushley again the man on target in the second half, he drifted away from his marker and his shot flew past Parr in the Town goal.
Institute marked their return to the Premier League with a well-earned point in a 2-2 draw at Dungannon.
They left it late with Stephen O'Flynn grabbing his second of the afternoon in added time to salvage a point.
While most of the games started in sunshine it was a sharp contrast to Stangmore Park with a heavy downpour before the kick-off.
The opening goal arrived in spectacular fashion with O'Flynn hitting the net from all over 25 yards out to give Institute the lead on 25 minutes.
That goal seemed to be all Institute would need but Dungannon stunned them with two quick goals, first Gary Liggett on 81 minutes and then Ryan Harpur tucked away a penalty.
Results in full:
Ballymena Utd 2-0 Warrenpoint Town
Ballymena Utd: Cushley 15, Gawley 52.
Cliftonville 0-0 Glentoran
Coleraine 1-1 Ballymena Utd
Coleraine: McDaid 83.
Ballymena Utd: McCartney 43.
Dungannon Swifts 2-2 Institute
Dungannon Swifts: Liggett 81, Harpur 84 (PEN).
Institute: O'Flynn 25, 93.
Glenavon 2-2 Crusaders
Glenavon: Bradley 53, Lindsay 73.
Crusaders: O'Carroll 18, Owens 78.
Portadown 3-0 Linfield
Portadown: Twigg 35, 57, Ward 64 (OG).