Thierry Henry urged Arsene Wenger to sign a top quality striker last season

Premier League: Arsenal v Manchester United Venue: Emirates Stadium. Date: Sunday, 4 October. Kick-off: 16:00 BST Coverage: Live on BBC Radio 5 live, plus live text commentary on BBC Sport website.

On the day Anthony Martial's status exploded as the teenager became a luxury-priced prospect for Manchester United, and Arsenal's vain summer search for an elite striker ended in disappointment, it was easy to reach the conclusion that the pool of established, talented forwards at the north London club was worryingly dry.

Both clubs had an easy £50m or so to spend on central strikers, and the best they could apparently come up with between them was a kid with a handful of goals to his name so far.

While Martial has been a revelation for United, a turbo-charged and cool-headed game-changer in terms of his impact on the team so far, Arsene Wenger was left examining internal solutions.

For Arsenal, who spent most of the transfer window like a teenager agonisingly watching the telephone to see if Karim Benzema's number would flash up, this was particularly frustrating.

Ever since the most prolific striker in their history, Thierry Henry, opined last April that Arsenal couldn't win the Premier League title without an upgrade in that department, the pressure to improve cranked up. "I'm afraid they need a top, top quality striker to win this league again," he said.

A tale of two strikers Olivier Giroud Theo Walcott Minutes played (2015 Premier League) 313 364 Goals 3 2 Assists 0 0 Shots 15 18 Shots on target 9 11 Sprints/90 mins 63.2 55.8

It was pretty clear, as far as Henry was concerned, that his compatriot Olivier Giroud was not in that "top, top quality" bracket.

It is telling that Theo Walcott was not really a major part of that conversation. At the time he was kicking his heels, mostly on the bench, trying to maintain the right mixture of patience and determination to take a chance when it came having spent a year recovering from a cruciate ligament injury.

More or less all of 2014 was spent rehabilitating, and changing his perspective as he became a father. Arsenal's first choice centre-forward? It was his ambition but it felt like a long shot.

Right now, ahead of a compelling challenge between Arsenal and Manchester United this weekend at the Emirates, the position feels like Walcott's for the taking. He has had to wait a long time to press his case. As he says: "I'll play anywhere, but the manager started playing me up front slowly."

Olivier Giroud reacts after his dismissal in the Champions League fixture against Dinamo Zagreb

Opportunities are now knocking. Wenger's inability to sign anyone in the last transfer window pushed Walcott up the pecking order, which appears to have been advanced even more by Giroud having a difficult time of it lately.

The Frenchman was jeered when he missed some chances for the national team, and sent off in Arsenal's defeat by Dinamo Zagreb in the Champions League, and Walcott looks to have eased in front. Giroud was the starter for the first two games of the Premier League campaign. But since then Walcott has started five of the last six Premier League and Champions League fixtures.

Former Arsenal striker Ian Wright recently called for Walcott to be given "a genuine run of games up there… let him prove he can do it".

He has responded by chipping in with regular goals and assists. His chance conversion still needs to improve, but 12 from 13 Premier League starts is not to be sniffed at. Once he got that unexpected berth to lead the line at the FA Cup final, in which he opened the scoring against Aston Villa, this was always going to be a key season.

His confident body language suggests he feels he belongs up front now and welcomes the responsibility. He also possesses a coolness of character which means he doesn't look affected if he misses a chance, and just concentrates on waiting for the next one.

Can he be the answer? It is still too early to say, but one thing that is clearly different about this campaign is Wenger's attitude towards a player he has worked on for almost a decade. For the first time the manager regards Walcott purely as a central striker.

Every minute of this season he has played so far has been in that role, not at all on the right flank he occupied for a long time, where he could sometimes get lost.

His performance against Leicester last weekend was full of the kind of movement to stretch defences, sharp runs, and strong interplay with team-mates that outline his case well.

The unconvinced point out that Leicester, with their high defensive line and cavalier style, are dream opponents for a speedy player like Walcott to whizz around on the counter-attack. The question of whether he can be as effective in tight home games where buses are parked and spaces squeezed remains in the balance.

If during that sequence of games Wright called for, he can learn to be effective, and make the difference, in those situations Arsenal really might be on to something.

Walcott mentioned Wright's style as an inspiration. "He obviously scored so many goals and caused havoc for defenders. He wasn't the tallest man in the world but the amount of pressure he would put on defenders just scared them," Walcott explained in an interview with Arsenal Player.

"I can learn from the runs he made, the pace he had in his game and his finishing. When he was in the box he didn't panic."

A connection with Alexis Sanchez is forming. As well as enjoying the space to dash into at Leicester, they created a goal for each other in the Champions League defeat by Olympiakos. It was a bright spot on a dark night for Arsenal, and a positive for Wenger to cling to as they prepare for United's visit.

Theo Walcott made his debut against Aston Villa in August 2006, when he was 17 years old

It seems extraordinary that the England forward will have been at Arsenal long enough to qualify for a testimonial soon. In January he will have been at the club for 10 years.

The manager sees a difference in the 26-year-old these days, and the influence he hopes he can bring. "When he arrived here he was a boy, a little boy who discovered a world where he did not know anything about it. He has become very mature, he has gone through difficult periods so he is a very strong man today. He can become a prolific goalscorer."

Henry, who spends so much time around Arsenal these days as he works on his coaching badges, will cast his eye over both Walcott and Martial with considerable interest this weekend.