Match ends, Wales 1, Republic of Ireland 0.
Wales ground out a 1-0 home win over the Republic of Ireland to stay top of their Nations League group.
The visitors edged a cagey first half, with chances scarce as these familiar foes looked like they might replicate last month's insipid goalless draw in Dublin.
Wales eventually came to life midway through the second half, David Brooks nodding in from close range after Gareth Bale's looping header across goal.
Brooks was denied a second goal by an outstanding save by Darren Randolph before Bale and Kieffer Moore missed further chances for the hosts, who extended their unbeaten run in competitive matches to 10.
Republic midfielder Jeff Hendrick was sent off in added time for bringing down Tyler Roberts as he appeared to have a clear run on goal.
A fourth victory from five Nations League matches keeps Wales one point clear of second-place Finland, who won in Bulgaria in Group B4's other fixture on Sunday.
Wales and Finland meet at Cardiff City Stadium on Wednesday. A draw would be enough for Wales to win the group and secure promotion to the top tier of the Nations League.
As for the Republic of Ireland, they remain third and a point in front of bottom side Bulgaria, who they host in Dublin on Wednesday in a match which will decide who is relegated to the third tier.
There was a distinct sense of deja vu about this fixture, a sixth meeting between the sides since 2017.
This had not been a rivalry to set neutrals' pulses racing; apart from Wales' 4-1 thrashing of the Republic in 2018, the other four games had produced just two goals.
That was no wonder as these were two teams who had struggled in attack regardless of opposition.
Wales had scored one goal in their past four matches in all competitions, while the Republic had mustered just a single strike in Stephen Kenny's first six games in charge.
At least Wales were still eking out results, with three 1-0 wins and a goalless draw - against the Republic, naturally - taking them to the top of Group B4.
But the Republic were without a win of any sort since a friendly victory over New Zealand a year ago.
Despite that disparity in form it was the visitors who started strongest in Cardiff, with Robbie Brady inches from scoring a fine opening goal as his powerful shot whistled just over the bar.
Wales then had their first meaningful effort as a vicious dipping free-kick from Bale brushed the top of the bar, before the Republic threatened again as James McClean's low shot was saved by Danny Ward.
The first half trundled to its goalless conclusion with little excitement, save for Wales midfielder's Joe Morrell kick out at Jayson Molumby, for which he was perhaps fortunate only to receive a yellow card.
Wales were too cautious for the first hour, their deep midfielders disconnected from their front three and wing-backs not pushing far enough forward against limited opposition.
However, assistant coach Robert Page - in temporary charge with Ryan Giggs absent - took the initiative by replacing left wing-back Rhys Norrington-Davies with striker Moore.
His introduction gave Wales more direction in attack and, as they lifted the tempo, they conjured the opening goal, Bale's intelligently weighted header finding Brooks, who powered his into the net.
The home side looked like they might kick on from that moment - with Brooks and Moore denied by Randolph either side of a Bale shot wide - but it mattered little.
Page's side were unconvincing for large parts of this match but relatively comfortable winners in the end.
They can now look forward to the chance to win promotion to the Nations League's top level, returning to Cardiff City Stadium on Wednesday needing just a draw against Finland.
Wales assistant manager Robert Page said:
"I think we gave the ball away cheaply in the first half. It was very frustrating and I said that to the players at half-time.
"We caused ourselves more problems than Ireland if I'm being honest.
"We invited pressure into our box and we gave cheap free-kicks away. That disappointed us a little bit.
"We decided to change the shape late on and it worked for us. We'll take the clean sheet, the three points and look forward to a big game on Wednesday.
"We've always had a plan B for if things aren't quite going your way and that was it again today."
Republic of Ireland manager Stephen Kenny said:
"I have no doubts I will be a success, absolutely no doubts.
"We have a clear vision of what we want. Between this camp and the previous camp, we have been in quite unprecedented circumstances, in modern times anyway. Certainly, it's quite unprecedented.
"Nevertheless, the players have come out against a good Wales team today and put in a good performance overall.
"We didn't create a load of chances, but you're not going to against a good Wales team. We probably had the better chances up to the last five minutes, when they had two on the break.
"We have to dust ourselves down and get ready for Bulgaria."
- 4DaviesBooked at 49mins
- 3N Williams
- 16MorrellBooked at 38mins
- 17Norrington-DaviesSubstituted forMooreat 62'minutesBooked at 65mins
- 7BrooksSubstituted forRobertsat 88'minutes
- 21Fon Williams
R. of Ireland
- 4DuffyBooked at 85mins
- 20O'SheaSubstituted forO'Dowdaat 82'minutes
- 22MolumbyBooked at 38minsSubstituted forHourihaneat 75'minutes
- 10BradySubstituted forByrneat 82'minutes
- 13HendrickBooked at 90mins
- 8HorganSubstituted forKnightat 59'minutesBooked at 80mins
- 9IdahSubstituted forCollinsat 75'minutes
- Petr Ardeleanu
- Shots on Target
Second Half ends, Wales 1, Republic of Ireland 0.
Jeff Hendrick (Republic of Ireland) is shown the red card.
Foul by Jeff Hendrick (Republic of Ireland).
Tyler Roberts (Wales) wins a free kick in the attacking half.
Corner, Republic of Ireland. Conceded by Joe Morrell.
Attempt saved. Kieffer Moore (Wales) left footed shot from the centre of the box is saved in the centre of the goal. Assisted by Tyler Roberts.
Kevin Long (Republic of Ireland) wins a free kick in the defensive half.
Foul by Tyler Roberts (Wales).
Foul by Jason Knight (Republic of Ireland).
Ethan Ampadu (Wales) wins a free kick in the attacking half.
Attempt saved. James Collins (Republic of Ireland) header from the centre of the box is saved in the centre of the goal. Assisted by Jack Byrne with a cross.
Conor Hourihane (Republic of Ireland) wins a free kick in the defensive half.
Foul by Daniel James (Wales).
Substitution, Wales. Tyler Roberts replaces David Brooks.
Attempt saved. James Collins (Republic of Ireland) right footed shot from outside the box is saved in the centre of the goal. Assisted by Jack Byrne.
Shane Duffy (Republic of Ireland) is shown the yellow card for a bad foul.
Foul by Shane Duffy (Republic of Ireland).
Chris Mepham (Wales) wins a free kick in the defensive half.
Corner, Republic of Ireland. Conceded by Chris Mepham.
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