Some storylines are simply meant to be. While Eduardo Da Silva’s importance to Arsenal last season was exaggerated, not least by Arsène Wenger seeking to explain his side’s alarming slump, no one would begrudge him last night’s triumphant return.

On his first start since suffering an horrific broken leg and dislocated ankle almost a year ago, the Croatia striker showed precisely what Arsenal have been missing, creating manifold chances for others and scoring twice to set up a fifth-round meeting at home to Burnley.

Whether Arsenal would have fared much better had Eduardo not been so seriously injured is doubtful and if their stuttering form will now improve significantly remains to be seen, but there can be no doubt he offers something different, as Wenger acknowledged.

“He was the star and everybody’s happy for him,” the Arsenal manager said. “He’s talented, intelligent and understands quickly what happens. That’s why he’s a striker. I’m not surprised he did well as he’s been extremely strong mentally over the last few months.”

Cardiff City could not cope with a resurgent Arsenal, whose ranks will soon be boosted further by the return of Theo Walcott and Cesc Fàbregas. Were it not for several superb saves from Tom Heaton, on loan from Manchester United, the visiting team would have been utterly humiliated.

Arsenal, who had scored a single goal in their previous four matches, were transformed into the free-flowing team of old, creating enough chances in the first half to rival the score that England’s cricketers were busy racking up in Antigua.

Eduardo was the catalyst. In this mood, as his sheer joy at taking to the field again was increased when it became clear that Cardiff were happy to give him the freedom of North London, the forward is two players in one: offering the predatory instincts of an Alan Smith with a creativity recently supplied around these parts by Dennis Bergkamp.

He demonstrated vision that the Dutch master would have been proud of as early as the sixth minute by splitting Cardiff’s defence with a cross-field pass to Carlos Vela, before attempting an audacious chip from the halfway line that floated just wide seven minutes later.

It was clear at this early stage that Arsenal were in the mood, with Kolo Touré and William Gallas having shots cleared off the line, but it was left to Eduardo to show the way to goal. The 25-year-old began the move himself as he dropped deep to receive possession in the 21st minute, playing an exquisite one-two with Vela that ended with him heading into the net from eight yards. His celebration showed what the goal meant to him, with tears welling up in his eyes.

“This was the best day of my life as it showed I can play again,” Eduardo said. “It was a special moment to score and I was very emotional.”

If Arsenal’s opener was a piece of poetry, then their second was more prosaic. Vela’s 35th-minute corner from the left was headed home by Nicklas Bendtner, but the Dane then blotted his copybook by hitting the post from point-blank range and then firing the rebound straight at Heaton.

This was Eduardo’s night, even allowing for Robin van Persie’s fourth in the final minute. The former Dynamo Zagreb player won a penalty after being fouled by Gavin Rae in the 60th minute and converted it himself, shooting to the right of Heaton before going to celebrate on the touchline with Tony Colbert, the club’s fitness coach. “Tony has spent more time with him than his wife so he deserves that kind of hug,” Wenger said.

As did Eduardo, after months of physical pain and mental anguish that few people can comprehend.