Following three defeats on the trot in the league, Mikel Arteta dropped Bernd Leno to the bench and Ramsdale started in their last two league wins against Norwich City and Burnley respectively.
The 23-year-old was particularly impressive in the Burnley game and made a couple of key saves in the 1-0 win at Turf Moor.
Nicholas pointed out that the goalkeeper has been under intense scrutiny since he joined Arsenal due to the fee the club paid to sign him from Sheffield United.
But the former Gunner is impressed with the authority he has shown inside the penalty box in the last two games.
Nicholas said on the Where’s Jeff podcast: “I was really pleased with the battling qualities of Arsenal.
“And I was particularly impressed with the goalkeeper. He seems to be an authority at the back and he has been questioned already in his early career at Arsenal.
“I am far more upbeat going into the north London derby this weekend.”
Arsenal will face Tottenham in a north London derby at the Emirates Stadium on Sunday.
It remains to be seen whether Ramsdale keeps his place in the starting eleven for the big game.
