Mikel Arteta was temporarily reassured after the victory against Sunderland. The reason was that after the defeat to Man United, Arsenal had then gone through 3 consecutive winless matches. The last two victories against Leeds and Sunderland helped the "Gunners" still firmly hold the top spot.
In the last two matches, Arsenal scored 7 goals and did not concede. Of those 7 goals, up to 6 G/As were made by substitute players, raising the total number of G/As made by substitute players to 16 from the beginning of the season in the Premier League. The team ranked 2nd in this list is Brighton with 14 times and Man City is the last team with only 2 G/As according to this criterion.
It's not until recently that the contribution of reserve players has been clearly felt from Arsenal, it has lasted throughout the season. Remember in September 2025, there was a time when Arsenal had to play 2 matches in 3 days, so taking advantage of reserve players to score or assist was something Arteta solved right from that time.

On September 13, 2025, in the match against Nottingham, Leandro Trossard assisted Martin Zubimendi in just 6 seconds after being brought onto the field. 3 days later in the match against Athletic Bilbao in the Champions League, Gabriel Martinelli also only needed 36 seconds to score after being assisted by Trossard. After that, he "prepared the feast" for the Belgian striker in the final minutes of the match.
In the first leg of this season against Man City, Eberechi Eze and Martinelli coordinated to create a goal in the final minutes, keeping 1 point for Arsenal. The following week, when Newcastle was leading 1-0 away from home, Mikel Merino came on as a substitute and scored the equalizer, before Martin Odegaard (also a substitute on the field) took a corner kick for Gabriel Magalhaes to score in the final minutes.
Among the 16 G/As that Arsenal's reserve players created from the beginning of the season, there were 6 times that brought decisive moments in the match (putting the team ahead or equalizing). The remaining 10 times do not seem to have much decisive significance but they help the "Gunners" feel more secure in the final minutes of the match, such as Viktor Gyokeres's most recent goal against Sunderland.
The most typical example is the away match against Bournemouth on January 3, 2026. After Arsenal was led, Bukayo Saka came on and assisted Declan Rice's 2nd goal and Arsenal's 3rd goal. After that, Bournemouth scored to narrow the score to 3-2. The match was very tense in the last minute but still had enough capital for Arsenal to finish with 3 points.
When commenting on how Gyokeres entered the field and scored in the victory against Sunderland, Mikel Arteta used the word "shooter" to describe this type of tactics. Martinelli is the best "shooter" of The Gunners with 3 G/As (2 goals, 1 assist). Although the Brazilian striker often plays on the left wing, all 3 G/As came from matches where he played on the right wing.
Mikel Arteta was once asked about letting Martinelli play on the right wing and sometimes letting Madueke or Saka appear on the left wing. The Spanish strategist only answered briefly, doing so would make Arsenal more unpredictable and much more flexible.
Each position has different physical and mental requirements related to each match plan. If you change a player's position twice or three times in a match, it means he has to take on 3 roles. I see some players in the team are more confident and comfortable than others when doing that.

At the beginning of the season, Gyokeres was forced to start a lot (first/20 matches) in the context of Gabriel Jesus and Kai Havertz being injured.
However, recently when Jesus recovered, Havertz also returned, Gyokeres was more on the bench, but every time he entered the field, it created danger to the opponent's goal.
Since Jesus returned in December 2025, Gyokeres has been on the bench for 10 matches, but that is very suitable for Arteta's current player usage.
As the championship race is approaching and most of the attack has recovered, ready to play, Arteta will need to continue to choose the right time for his ability to control the match more effectively.