Eddie Jones compared Wales' threat of a comeback in England's 24-13 victory over Wales at Parc y Scarlets to watching the horror film 'Psycho'.
An 11-7 lead failed to reflect the visitors' control of the first half and a hard-fought third quarter was fraught with danger as Wayne Pivac's men threatened a comeback when successive Dan Biggar penalties reduced the deficit to 18-13.
But England powered home through the boot of Owen Farrell to secure their place in the Autumn Nations Cup final, which will be played in front of 2,000 fans at Twickenham next Sunday.
"At halftime it could have been a 'Psycho' horror movie. The woman goes to the shower and you know what's coming from behind the shower curtain," head coach Jones said.
"Wales did a few things at the end of the first half to put us off our game and then we had a choice at halftime of how would we react. Would we allow them to continue to do that or do we stick to our game?
"The boys showed really good tactical discipline to stick to our game. We had one little wonky period for around 10 minutes in the second half but generally we had game control so I was really pleased about that."
England's last defeat was against France at the start of the 2020 Six Nations - a competition they subsequently won - and since then they have compiled a series of solid if unspectacular wins.
Jones, who saw Henry Slade and Mako Vunipola touch down for his pre-match favourites, wants to end the year with a bang.
"We don't feel like we've played our best rugby yet so it's our last game. It's our grand final of 2020 and we want to make sure we put on our best performance," Jones said.
Wales head coach Wayne Pivac struggled to mask his frustration with referee Romain Poite following a seventh defeat in the last eight Tests.
"Dan Biggar was clearly taken in the air. The TMO (television match official) comes in and calls that, but he is over-ruled by the man in the middle," Pivac said.
"We then asked for him (Poite) to have a look before the conversion was taken, but our captain was dismissed 20 metres away.
Asked if Wales would raise issues with World Rugby, Pivac added: "We've been doing it every week, to be honest with you."
Australian Associated Press
