It took Harry Kane four games and 269 minutes to even manage a shot on target at the 2022 World Cup in Qatar.

He looked tired early in that tournament and I felt he needed a rest after England's first two matches.

Things could not be more different this time - he will be on top of the world after scoring twice in the 4-2 win against Croatia.

As a striker, the one thing you desperately want to do at any major tournament is get off to a good start.

I was lucky enough to do that myself for England when we beat Tunisia in our first game at the 1998 World Cup.

Honestly, it was a massive relief - not only for the team to get the win, but to get on the scoresheet myself, as captain and our main goalscorer, when everyone was looking at me to deliver.

For all the same reasons, I know Kane will be feeling exactly the same way after the way he played on Wednesday.

He had to sit all week with the rest of the England squad and watch all the other games, seeing superstars like France's Kylian Mbappe, Norway's Erling Haaland and Argentina's Lionel Messi get up and running, not just with one goal but by scoring at least two.

Kane would have been absolutely desperate to join the party and get off the mark in his first game too, so to do that after only 12 minutes and go on to get another one as well, is huge for him - and for England.

When Kane finally got a shot on target in Qatar, in the last 16 against Senegal, he scored.

This time he has got that feel-good factor from the very start, and we've already seen what he does when that happens - at Russia in 2018, Kane scored five goals in England's first two games to send him on his way to the Golden Boot and help us reach the semi-finals.

With arguably our toughest game in Group L out of the way and Ghana and Panama next, his eyes must be lighting up.

'Kane looks fitter and stronger than before'

As well as his goals, it's brilliant to see Kane looking in peak condition.

After his slow start in Qatar, I didn't think he was 100% fit at Euro 2024 either, and we also struggled to get the best out of him at that tournament because of the way the team was set up.

Then, whenever he dropped deep to get on the ball, there was no-one up front for him, or anyone else, to find with an out-ball. He also brought an extra defender back with him into midfield too, so there was less room and time for England in those areas.

Now, under Thomas Tuchel, it's different. England are using Kane a lot like Bayern Munich do.

Tuchel has managed Kane before, at Bayern, so he knows how to get the best out of him and also understands that doing that is integral to England's hopes in the United States, Canada and Mexico.

When he came back looking for the ball against Croatia, Noni Madueke, Jude Bellingham or Anthony Gordon were running past him and flying forward to cause problems for defenders with their pace and energy.

The other difference, though, is Kane himself. He is still playing the same way, but to me he looks fitter and stronger than before.

He's come into this tournament off the back of a brilliant campaign for Bayern Munich and looks very sharp and very confident - as you would do after scoring 61 goals in one season.

Those numbers are just ridiculous by the way. I heard Kane talking about it the other day and he said he had scored 20-odd more goals this time than he had ever done before.

When I made my professional debut for Southampton in 1988, if you just got 20 goals full-stop then that was deemed a success. Kane was already hitting some huge numbers anyway, for Spurs then in Germany, and then he added another 20 on top.

That kind of form is why so much of England's hopes rest on his shoulders. As our captain and best player, he carries a lot of responsibility - but he clearly enjoys it.

'Kane showed his mental strength too'

Kane still works hard for England defensively. The other night he was blocking a shot one yard off his own goalline in the last minute - but crucially he has not stopped scoring either.

He got a little bit of luck with the retaken penalty that got him started against Croatia, but even that showed his mental strength.

I've not been in a scenario like that where I had to take the same spot-kick again, but I have had two penalties in a game at a World Cup - against Argentina in 1998 when I had one in normal time and one in the shootout, and beat Carlos Roa twice.

It's such a difficult situation before you take the second one, because there are so many things going through your mind.

You are trying to second-guess what the goalkeeper will do, and he is trying to do the same to you, but at the same time you are battling negative thoughts about whether you will miss.

For Kane to get over all of that, and then put his second penalty in exactly the same spot as the first one which had been saved, takes some doing.

Then there was his header, and what a brilliant header it was.

First and foremost it was a great ball in from Declan Rice, and while Croatia's defending was poor, Kane made the absolute most of it. He read the line of the ball so quickly and then executed his finish perfectly.

'Of course he will be thinking about another Golden Boot'

After making such a fast start, of course Kane will be thinking about another World Cup Golden Boot already - any striker in his shoes would be.

Along with France's Mbappe and Colombia's James Rodriguez, he is one of only three players at this tournament to have a special patch on his sleeve, showing he has won one previously.

I know the mentality of a goalscorer, and there is no doubt that Kane will be absolutely desperate to be the first player to win it for a second time. So will Mbappe though, and of course Messi and Haaland will have an eye on the prize too.

Those three are all great goalscorers, but while they are all very different types of players, what they have in common is that their teams are set up to get the best out of them, just as England are now with Kane.

So, the race is on. It's far too early to try and call it, but I am just delighted Kane is in the mix - if we are going to go far at this World Cup we will need him at his best.

Alan Shearer was speaking to BBC Sport's Chris Bevan

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