And Putin certainly had an amusing reaction when Russia opened the scoring through Iury Gazinsky early on.
Presumably Bin Salman felt there had been a foul on a Saudi defender in the build-up to Gazinsky's header, as he appeared to be protesting to his two neighbours.
Both responded with a shrug and an open-handed gesture, before Putin and Bin Salman made up by shaking hands.
ITV commentator Clive Tyldesley quipped: "They're doing an oil deal, it's nothing about football."
Tyldesley completed a full house of Russian World Cup bingo in the first-half by also mentioning that Stalin had a good moustache and referencing a "popular Russian TV presenter who actually looks like Borat".
A VAR-CICAL NUMBER OF OFFICIALS
World Cup history was made in Moscow with the Video Assistant Referee (VAR) technology available for the first time at the tournament.
But one side-effect was the ridiculously long list of officials deployed at the game — and indeed all 64 games in the World Cup — by FIFA.
In addition to the usual referee, two assistants and fourth official, there is also a reserve assistant referee, match commissioner and general co-ordinator inside the ground.
Then you have a further four VAR officials watching the match on a bank of video screens — the actual video assistant referee, an assistant, one for offside decisions and one in support.
So that's 11 in total — perhaps they'll field a team at some point.
What's more, they're all from different countries so presumably there's a few translators involved as well.
Welcome to FIFA's brave new officiating world.
RONALDO IS THE STAR OF THE OPENING CEREMONY
Any World Cup opening ceremony needs some footballing royalty to make things go off with a bang and Brazilian legend Ronaldo certainly fitted the bill here.
Dressed smartly in a suit and tie, the 1994 and 2002 World Cup winner helped deliver the official match ball on to the field at the Luzhniki Stadium before kick-off.
At one point he shaped to smack the ball at furry mascot Zabivaka, only to feint at the last moment and allow a fortunate small child to kick it instead. What a gent.
THE FIRST OF MANY MEXICAN WAVES... AFTER JUST FOUR MINUTES!
Usually the inevitable consequence of a boring football spectacle is the Mexican wave.
But Russia vs Saudi Arabia had barely even started when the first Mexican wave was started just four minutes in.
We can only assume this will be a regular feature of this World Cup.
