And the hosts were made to pay after two defensive errors in quick succession.
Ramsey's free kick was heading towards Vokes, who was winning his 50th cap on the night, when Portuguese referee Manuel de Sousa spotted a foul on the big Burnley striker and pointed to the penalty spot.
The goal sparked clashes between both sets of fans before Ben Davies produced a vital interception in injury time as Wales survived until half-time with their 1-0 lead in tact.
The signs were ominous for Wales when Aleksandar Kolarov curled a free-kick inches wide but Vokes nearly snatched a second with his head moments later.
But Wales took a 35th-minute lead after Serbia goalkeeper Vladimir Stojkovic had inexplicably allowed the ball to run across his body and brought down Ramsey on the edge of his box in a wide position.
Serbia finally got their reward for relentless pressure after 73 minutes when Mitrovic, an aerial threat in the box throughout the contest, collected a loose ball and fired it past Wales keeper Wayne Hennessey from seven metres.
"It was a tough game but, overall, we'll be happier with a point than Serbia". You aren't going to come here and play open football, we did that before and you know what happened.
"But we are at home, we hope the Bernabeu will be a fortress and, at the end of the day, it is in our hands".
"I can't fault the players, they worked so so hard".
It was Edwards who had the first real chance but he failed to get enough power on his header from Joe Ledley's fourth-minute corner. You have to deal with it at worldwide level, and we've experienced it before home and away. The latter is a leader in the team, and it will likely not be able to help his team in the upcoming match, and if they come out on the field, it will be far from his best form. "Two things stand out: the respect we showed Slovakia when their national anthem was played - it was silent from us, which was great; and then with our national anthem ... the noise, wow, that was unbelievable". It will go down to the wire. Absolutely. One hundred per cent we can bridge that gap. "One hundred per cent".
President Trump to bring back harsher restrictions on travel to Cuba
Trump will not go so far as to sever diplomatic ties with Havana or shutter the US embassy that reopened there in 2015. The new Trump policy will also prohibit most commercial transactions that allow money to flow to the Cuban military.