Needing at least a draw to have a chance of progressing into the play-offs, Wales were undone by a resolute Republic of Ireland, who soaked up pressure, scored on the break through James McClean on 57 minutes and then defended for their lives to hold on to the 1-0 win.
It was a rare home defeat in qualifying for Wales in recent years and left them third in European qualifying Group D. Serbia beat Georgia to book their place in Russia next summer while the ROI now await their play-off opponents with matches played next month.
Ben played the full 90 minutes in Cardiff.
Japhet Tanganga played the full match as England Under-19s drew 2-2 against Slovakia in a friendly.
Below: Hugo at France's pre-match press conference on Monday
Make or break time
The World Cup hopes of Hugo Lloris, Moussa Sissoko, Davinson Sanchez and Vincent Janssen are on the line this evening.
Hugo and Moussa know victory for France in their final qualifying match against Belarus in Paris will secure a place in the finals in Russia next summer.
France will be favourites to complete their task at the Stade de France. Les Bleus top European qualifying Group A by a point from Sweden - who face Vincent's third-placed Holland - having won six of their nine matches so far, losing only once. Belarus have won just once and lost six.
However, there is a warning - France were held to a shock goalless draw by Luxembourg only last month.
Vincent, currently on loan at Fenerbahce, will need his shooting boots in Amsterdam. Holland need a footballing miracle really, they have to beat Sweden and turn around a 12-goal goal difference - therefore win by seven goals - to take second place.
Davinson Sanchez faces a thrilling final match with Colombia in South American qualifying.
There are 10 teams in the qualifying process with the top four going directly to Russia and the fifth-placed team facing a play-off.
As it stands, Colombia are fourth on 26 points and Peru fifth on 25 - and the pair meet just after midnight in Lima.
The last round of results has opened the door for Argentina, currently sixth on 25 points, to move into the top five with a win against Ecuador as one of Colombia/Peru, or both, will drop points.
It's also a big night for Jan Vertonghen as the defender will break Belgium's appearance record if selected for the Red Devils' final qualifying match against Cyprus this evening. He joined Jan Ceulemans on 96 caps when he started against Bosnia & Herzegovina on Saturday.
Tuesday 10 October
Toby Alderweireld and Jan Vertonghen - Belgium home 2018 FIFA World Cup qualifier against Cyprus - kick-off 7.45pm
Hugo Lloris and Moussa Sissoko - France home 2018 FIFA World Cup qualifier against Belarus - kick-off 7.45pm
Vincent Janssen - Netherlands home 2018 FIFA World Cup qualifier against Sweden - kick-off 7.45pm
Heung-Min Son - South Korea friendly against Morocco in Switzerland – kick-off 2.30pm
Josh Onomah and Kyle Walker-Peters - England Under-21s away European Under-21 Championship qualifier against Andorra - kick-off 5pm
Marcus Edwards - England Under-20s home friendly against Czech Republic - kick-off 7pm
Jack Roles - Cyprus Under-19s home European Under-19 Championship qualifier against Azerbaijan - kick-off 1pm
Wednesday 11 October
Davinson Sanchez - Colombia away 2018 FIFA World Cup qualifier against Peru - kick-off 12.30am UK.
TJ Eyoma and Tashan Oakley-Boothe - England Under-17s FIFA Under-17 World Cup Group F match against Mexico in India - kick-off 12.30pm