Francis’ early try – no Wales prop had previously touched down in Tests against South Africa, New Zealand or Australia – sent his team on their way to a 20-11 victory over the Springboks.
Wales extended an unbeaten run to nine games – their longest winning sequence since 1999 – and they have not lost at home for a year.
It augers well for a Six Nations campaign that begins against France in Paris on February 1, with former Doncaster Knights prop Francis, who had never scored a try for Wales or his club Exeter, enthused by what lies ahead.
“Winning is a habit and, as a squad, we believe,” he said. “Everyone works for each other, and we are on a good run at the minute. It is a squad you want to be involved in. The atmosphere is unreal.
“It was a great feeling to score a try – it is not something I do very often. I think the last one was when I played for London Scottish or Doncaster.”
Sean Maitland’s try ensured Scotland ended their autumn campaign on a high as they edged out a misfiring Argentina side 14-9 at Murrayfield.
Defeats to Wales and South Africa left Gregor Townsend’s side in danger of losing momentum ahead of the Six Nations.
But they got back on track as Maitland’s second-half touchdown and nine points from captain Greig Laidlaw ensured they held off the Pumas.
Andrew Conway’s hat-trick sealed Ireland’s second-straight autumn series clean sweep with a 57-14 win over the USA in Dublin.
The biggest surprise of the final weekend of the Autumn Internationals came in Paris where Fiji claimed their first ever win over France with a surprise 21-14 victory at the Stade de France.