Brennan Johnson thinks Wales deserve to be on the big stage after pushing Belgium all the way in the Nations League.
Wales lost 2-1 in Brussels on Thursday against the world second team to stay bottom of Group A4 with one game to play.
But Wales will avoid relegation to League B if they beat Poland in their final game in Cardiff on Sunday.
“It was a two-half game,” said Johnson, whose fascinating run and cross set up Kieffer Moore’s headed goal that set the tone for a better Wales performance in second half after Belgium took a 2-0 lead at the interval.
“In the first, we lacked a lot of conviction. We didn’t know how good we could be that night, and especially what we could bring in the future.
“We didn’t show any of that. In the second half we came out with a different mentality and made each other proud.
The Nottingham Forest striker added on S4C: “Rob Page (Wales manager) told us to believe in ourselves, to show why we are here, and I think we have.
“Poland is a huge game to stay in this league. It will be a very big game and we will all be ready for it.”
Over 30,000 fans are expected to give Wales a start at the World Cup at the Cardiff City Stadium on Sunday.
The game against Poland will be Wales’ last game before the World Cup in November, the Dragons’ first final appearance since 1958.
Defender Rhys Norrington-Davies said of the loss in Brussels: “We changed our form in the second half and we were much more compact.
“Win now on Sunday and we stay up, so all the attention is on this game. The immediate objective is to stay in the top group of the League of Nations.
“In the last Nations League we played some good teams. But it’s a huge step forward and that’s what we want to do next time.”
This is Wales’ first campaign at the top level of the Nations League, having won their group at the second tier last time out.
Wales were not helped by the fact that Page had to field second-tier sides in June as they prepared for what would prove to be a historic World Cup play-off victory against Ukraine.
They will again be without injured quartet Aaron Ramsey, Ben Davies, Harry Wilson and Joe Allen on Sunday. Chris Mepham and Ethan Ampadu are also suspended after picking up bookings in Brussels.
But skipper Gareth Bale is in line to start after coming on as a 64th-minute substitute against Belgium.
Bale had just one training session after joining camp late on Tuesday after playing for Los Angeles FC the day before.