Five talking points from the Japanese Grand Prix after Lewis Hamilton's victory on Sunday:

HOW MANY FERRARI MECHANICS DOES IT TAKE TO CHANGE A PLUG?

The sight of Ferrari team boss Maurizio Arrivabene looking glumly at the floor after Sebastian Vettel's early retirement told a story in Suzuka. A week after a fuming Ferrari president Sergio Marchione spoke of "organisational changes" for a string of costly mistakes in recent races, it would be little surprise if heads roll at Maranello. The fiasco surrounding Vettel's retirement after just four laps -- caused by a humble spark plug -- sounds like the punchline to a bad joke.

GET A ROOM!

After sharing the podium with Max Verstappen and Daniel Ricciardo in Suzuka, race winner Lewis Hamilton noted the banter between Red Bull pair and smiled: "I've never seen drivers such great friends. Do you guys share a room?" Hamilton's relationships with his own team-mates have largely been more fractious (honourable mentions: Fernando Alonso and Nico Rosberg). Verstappen, who had given Hamilton a late fright in the race, didn't bat an eyelid. "Yeah we actually share a bed," he replied.

SEB KEEPS HIS COOL

Vettel would have been well within his rights to throw his toys out of the pram after Ferrari's latest mechanical failure. The German may have been hopping mad as his title hopes were frazzled by a faulty spark plug but he coolly held it together in his TV interviews. "I need to protect (the team) -- they've done an incredible job," said Vettel. Compare that to Hamilton's histrionics last year when he suggested Mercedes could be conspiring against him after an engine fire in Malaysia.

OVER AND OUT FOR PALMER?

Jolyon Palmer admitted he may never return to Formula One after completing his final drive for Renault with a 12th-place finish in Japan. The Briton, who makes way for Carlos Sainz, faces an uncertain future and may need to explore options outside of F1. "On the plane back home it will probably sink in," he said, despondently, although the sight of Sainz crashing his Toro Rosso into a wall on lap one will surely have made him feel a little better.

NAUGHTY 'NANDO'

You just can't keep Fernando Alonso away from controversy. This year, he managed to avoid turning the airwaves blue over team radio at Suzuka, home of McLaren's engine suppliers Honda, after a profane outburst 12 months ago. But the Spaniard got into hot water for interfering with the battle between Hamilton and Verstappen in the closing stages of the race. Alonso, who was fighting for 10th with Felipe Massa, ignored blue flags ordering him to get out of the way, earning him a couple of penalty points.