It looked as though Portugal would lose its perfect record in Group F when Ronaldo saw a spot-kick saved by Caoimhin Kelleher, but Neves's first senior international goal broke Irish hearts at the death.

Portugal's first real attack saw Ronaldo strike the base of the post from the edge of the area, and Bernardo Silva somehow failed to turn the rebound into a gaping net.

Vitinha saw an attempt from distance deflect onto the top of Kelleher's net as Portugal continued to dominate possession, but Ireland made it to half-time at 0-0 as its goalkeeper made a sprawling save to keep out Ronaldo's header at his near post.

Portugal continued to boss proceedings in the second half, but Ronaldo scuffed wide after taking in Bruno Fernandes' pass with a lovely touch, while Kelleher got down to his left to turn Vitinha's curler around the post.

The hosts' best opportunity came when substitute Francisco Trincao cut inside and fired off a shot that crashed into Dara O'Shea, with referee Ivan Kruzliak immediately awarding a penalty for handball.

The decision stood after a video assistant referee (VAR) review, but Kelleher flicked out his left leg after diving and turned Ronaldo's weak spot-kick over the crossbar.

But in the first of seven minutes of second-half stoppage-time, Neves proved the hero, getting ahead of Kelleher to nod Trincao's in-swinging cross home and lift the Selecao to nine points.

Asked if his goal was destined to arrive this way, Neves, who displayed a tattoo of himself with Jota on his calf when celebrating, said: "I think so.

"My first goal for the national team, with this number, it couldn't have come in a better way.

"That desire and passion he had to be here with us. I said that each one of us was going to inherit a little bit of who Diogo was, and today was a game like that.

"It was a very difficult game, against a team defending extremely low, with practically no space. It had to be this way."

This was Portugal's first at home since Jota's death, and the 21st minute of the game saw fans at Estadio Jose Alvalade applaud in tribute to the late Liverpool forward.

"Of course, it was special for Ruben to score, but it also would be for anyone," Trincao added. "In the 21st minute, I was out warming up and feeling the support of the fans, it's always very beautiful.

"This group is more united than ever, and now we have to win the next game."

Portugal can seal qualification for the FIFA World Cup if it beats Hungary on Wednesday (AEDT), and Neves is determined to get the job done with two games to spare in Group F.

"We think game by game," he said. "We can close qualification for the [FIFA] World Cup in the next game, and we will do everything to achieve that."