Mikel Arteta said his Arsenal side are in need of January reinforcements as they lost further ground on league leaders Liverpool after blowing a two-goal advantage over Aston Villa.

Arsenal were leading 2-0 after 55 minutes at the Emirates Stadium, with goals from Gabriel Martinelli and Kai Havertz, but were once again damaged by former head coach Unai Emery as Villa fought back to claim a point.

With Arsenal’s executives working hard to recruit another attacker this month, Arteta admitted after the game that his team is “very short” of options. Arsenal have seven players missing through injury and had three academy players on their bench against Villa.

The Arsenal manager also compared his situation to that of Liverpool, who secured a late victory over Brentford after substitute Darwin Núñez scored twice after coming off the bench.

“Obviously they managed to do that [find the winning goals],” said Arteta of Liverpool. “They made the subs and the subs made the impact, and they managed to change the game. And in our side, it was the opposite.”

Arteta insisted he was “incredibly proud” of his team’s dominant performance against Villa, given the physical load that has been placed on his available players in recent weeks, but also conceded that Arsenal cannot compete for titles if they continue to make sloppy defensive errors.

Thomas Partey, playing as a right-back, was at fault for Villa’s second goal after losing sight of striker Ollie Watkins in the penalty box.

“I am incredibly proud of the team,” said Arteta. “I think it was an immense performance. I cannot be prouder of that [but] defending the way we did, for one of the goals especially, it cannot be part of our game if we want to be at the highest level in this country.”

Arsenal briefly thought they had found a late winner when Mikel Merino’s strike deflected into the net off Havertz, but replays showed the ball had hit the Arsenal striker on the arm.

The draw meant that Arsenal have dropped 12 points from winning positions in the Premier League this season, their most in a single campaign across the last five years, although Watkins did have sympathy for the home side after seeing a replay of the disallowed goal.

“Seeing it back there, I’m not sure,” Watkins told Sky Sports. “If that was against me I’d be a little bit disappointed. I don’t know, from that angle I’m not sure. That’s what VAR is for. We got the goal and got a lot of momentum from that. They were quite open and there were chances to be had.

“We knew they went man for man. There were a few times where I could have done better, I was one-on-one with Gabriel a few times. They are always a little bit open. When I got my goal, I felt like we had enough time to push on and get a goal.

“It was about being brave and making more passes. Once we got it down and made a few passes, that’s when you can catch them.”

‘We trust in ourselves, and have to keep going’

Arsenal’s injury crisis has worsened in recent days with the loss of key centre-back William Saliba to a hamstring problem. “I think tomorrow we will have more information,” said Arteta. “For sure [we are worried]. Especially with the numbers that we have in the squad and looking at our bench. Very worried.”

Martinelli insisted that the Arsenal players still have “trust” in each other and said there is still a long way to go in the title race.

“It’s a disappointing day,” he said. “We wanted to win the game, but we have to keep going. We trust in ourselves, and we have to keep going and improving. It is a long journey to go. We have to focus on ourselves.

“That’s football, that’s the Premier League, the most difficult league in the world. We know our qualities and we know the potential we have and we trust in ourselves.”

Emery said: “We competed well. To get something here is very difficult. To compete like we did is the only way. They were controlling and pushing more [earlier on]. We had to defend strongly.

“The second half we reacted well. The mentality we showed is the mentality we want. We needed the goalkeeper, the defenders. We were always trying some transitions. Fantastic job. Now we are in good balance. We are fighting with really strong teams. How we started the second part of the season has been good.”

Merson slams Partey’s ‘atrocious’ defending

Arsenal great Paul Merson joined in the criticism of Thomas Partey for his “atrocious” defending following his costly lapse in concentration for Villa’s equaliser.

“I’d be shocked now if Liverpool didn’t go and win the league,” Merson told Sky Sports.

“They shouldn’t have needed that spark, they were 2-0 up and the defending for the goal, especially the Partey goal, is just not good enough. You’re 2-1 up, they’ve got back in the game, then you’ve got to be solid. You’ve got to hang on, you’ve got to try everything you can, you’ve got to pick players up, and for me it’s too easy. It’s too lackadaisical.

“If you want to win Premier Leagues you’ve got to be on it every day of the week, every weekend, every game you’ve got to turn up and make it hard. When you’ve got your back to goal like Partey for the second goal, it’s atrocious.

“To win a Premier League, or any league, it’s hard. You’ve got to keep on turning out week in, week out. Anyone can win a cup, the draw wins you the FA Cup, the draw wins you the Carabao Cup. But the league is week in, week out, you’ve got to be prepared to put yourself there and defend and make sure he doesn’t score. Both goals, [Mikel] Merino just lets [Youri] Tielemans run past him, and then Partey.”

‘Liverpool have that little bit extra’

Merson’s Sky Sports co-pundit Lee Hendrie agreed with his colleague’s criticism of Arsenal’s title credentials. “You look at Liverpool today and you think they’re going to come away with a point from Brentford, but they’ve got that little bit extra to go and get two goals at the end and probably could have been three or four.

“But I’m just looking at Arsenal and they do not have that X-factor that’s going to go and get those results. If they go and get a third and win 3-2, you start to think ‘is it Arsenal’s, can they go on a good run?’.

“It’s not impossible but I think games like tonight, that’s where you reflect on seasons where 2-0 up, at the Emirates at home, you should be comfortable. We sat and said this should end up… and the Arsenal of old would probably have gone and won 3-0 or 4-0 comfortably.

“Credit to Villa. I thought they were excellent in the first half. They were going to come up against it again in the second half which they did, but to come back from 2-0 down, you can have that mindset of you’re away from home, you’ve got a midweek game coming up, do you sit back and accept defeat? They didn’t, they kept going and he made a couple of changes, tweaks, and once you get that next goal you give yourself that opportunity and that’s what they did with Tielemans getting that first goal for Villa.”