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Rune has fallen from a high of four down to number 15 in the ATP rankings and was unable to hold on to a lead in his match with Thompson in London.

Australian Thompson fought back to prevail 4-6 7-6 (7-4) 6-3 in an entertaining encounter against the seventh seed.

Rune made the semi-finals at Queen's and the quarter-finals of Wimbledon last year, but is now seriously lacking momentum as the third grand slam of 2024 fast approaches.

Elsewhere at the ATP 500 event, third seed Grigor Dimitrov is safely through after cruising past Adrian Mannarino 6-1 6-2 in only 63 minutes.

Dimitrov will face either Sebastian Korda or Karen Khachanov in the last 16. 

Top seed and defending champion Carlos Alcaraz starts his campaign against Argentine Francisco Cerundolo. 

That is also when Thompson’s compatriot and last year’s runner-up Alex de Minaur begins his tournament with what could be a testing clash against Italian Lorenzo Musetti.

In the first career meeting between the two players, both Rune and Thompson were strong on serve. The three sets only produced two breaks – one from each player – in a battle that topped the two-hour mark.

Thompson came into the tournament on a five-match losing streak, but has often impressed on grass, with this being his 64th career win on the surface.

He had eight aces to just one double fault and crucially won 69 per cent (20/29) of his second-serve points, affording Rune just one break-point opportunity across the whole match.

Thompson added 27 winners and could face home hope Andy Murray next round if the Briton can defeat Alexei Popyrin.

As for Dimitrov, he recorded 28 winners and only five unforced errors in his impressive win over Mannarino. Having made the quarter-finals at the French Open, the Bulgarian looks poised to enter Wimbledon in good form.