Misfiring Gunners pay for lack of striker once again

Alexandar Isak celebrates after scoring against Arsenal during the League Cup semis first leg at Emirates Stadium. [AFP]

Newcastle took a giant stride towards the League Cup final as goals from Alexander Isak and Anthony Gordon earned a 2-0 semi-final, first leg lead at Arsenal on Tuesday.

The Magpies have never previously won the competition and have had to wait since 1969 to celebrate any major trophy.

But in Isak they have the form striker in England right now and he rifled home the opener then helped tee up the second for Gordon.

Arsenal have a mountain to climb when the sides meet for the second leg on February 5 if they are to progress to meet either Tottenham or Liverpool in the final.

"It's massive. it's a great result but it's only the first half," said Isak after Newcastle's seventh consecutive win and first at the Emirates since 2010.

"If we don't go through then this has no meaning."

The importance of silverware to both clubs was reflected in the line-ups as Mikel Arteta and Eddie Howe named their strongest available teams.

Arteta has brought Arsenal back into contention for Premier League titles in recent seasons, but his only trophy in charge of the Gunners came five years ago by lifting the FA Cup in the early months of his reign.

The home side were able to welcome back Kai Havertz, Martin Odegaard and Gabriel Martinelli from the side that started Saturday's 1-1 draw at Brighton.

But Arsenal's lack of a lethal striker like Isak proved the difference between the sides.

Arsenal had the majority of the ball and the chances but failed to make them count.

"That was the biggest difference in the game. In every other aspect, we were the better team," said Arteta on his side's wasted chances.

"I have full belief. I have seen my team playing against them. I believe we can do it!"

Martinelli came closest when he raced onto Leandro Trossard's pass and smashed against the post.

Moments later came the sucker punch. Arsenal, so renowned for their own set-piece threat, allowed a long free-kick into their box to fall at the feet of Isak who fired in off the underside of the bar.

The Swede's 14th goal in his last 15 games took him to 50 in a Newcastle shirt -- doing so in five fewer matches than it took the club's record goalscorer Alan Shearer.

Isak had a major role to play in what could be a decisive second goal in the tie just after the break.

This time the Newcastle striker's quick feet allowed him to get a shot off that was parried by David Raya into the path of the onrushing Gordon to fire in the rebound.

Arsenal should still have made their mammoth task for the return leg in Tyneside next month a more manageable one.

Havertz somehow miscued a header wide with the goal gaping to cut the arrears.

Howe replaced Isak and Gordon as Newcastle were happy to just to protect their lead in a 5-5-0 formation for the final 20 minutes.

Arsenal, though, lacked the guile to break them down without the injured Bukayo Saka to seemingly extend their wait for Arteta's revolution to deliver another trophy.