What was a superb battling draw against 2006 World Champions Italy at Windsor Park could have been even better had the Sunderland man put away a gift of a header in the first-half.
Healy, who has notched up 35 goals in the green shirt, looked certain to make it 36 when he ghosted in at the far post to meet Chris Brunt’s centre but somehow missed the target when it looked easier to score.
He has now failed to score in eight qualifiers and was replaced by Kyle Lafferty midway through the second half.
Worthington though is standing by the record-breaking marksman.
“I was blowing David's header in,” he admitted. “It was a great ball in by Chris Brunt. The little man found a little gap but he is just going through a lean spell.
“I will carry on supporting him because he is working hard in training and looks a lot brighter and sharper. It is a case of when it happens.”
In showing just how far Northern Ireland have come in recent years, Worthington also revealed his side were left dejected at failing to beat the Azzurri.
As well as Healy’s miss, Steven Davis went close in the dying seconds, while Stephen Craigan had what looked a cast-iron penalty turned down when his centre struck the hand of Daniele De Rossi but the French referee Tony Chapron waved away the Motherwell defender’s protests.
Worthington said: “It was a performance with a lot of character, determination and resilience. The discipline in the team was fantastic. Everyone stuck to their task.
“We knew Italy would have a lot of possession and one of the pleasing things for me is that the players are disappointed they have not won the game.
“They feel we had the better chances. That shows to me what the players' mental state is.
“Also we have not played as well as we can do, which is passing the ball.
“It is a great point against the ex-world champions.”
It was Northern Ireland's second clean sheet in the campaign following the 1-0 victory against Slovenia last month and they will travel to the Faroe Islands for the match on Tuesday in good heart.
Worthington said: “Two clean sheets in the first two games is very pleasing. We stuck to our task, we kept our shape and gave nothing away.
“We have a good group of players and a lot of hard work goes in. I would have loved to have won the game but make no mistake a point against Italy at home shows we are moving forward.”