He said: "The club means so much to me. I've been here since I was six-years-old. Jonny is a local guy who has come through the academy and it's important to keep that local influence in a team.
"He has worked hard to make his way into the first-team and I aspire to be like him."
The 18-year-old replaced Arr in the latter stages of the Leicester clash in front of almost 10,000 people at Sixways.
And the former King's School pupil says he was delighted to get his Sixways career off the mark.
He continued: "It was a great experience for me to make my Warriors debut in front of such a big crowd.
"There were lots of positives to take from the game. It was an impressive performance from the boys and one of the best we have produced this season."
Academy youngsters Dean Hammond, Ben Howard and Max Stelling have also been given opportunities in the Warriors first-team, as the club looks to build for the future.
And with academy players training with the senior players, De Cothi insists the youngsters are benefiting from spending time with their more experienced colleagues.
He concludes: "My aim is to keep training with the first-team squad and to keep learning from players like Jonny, Paul Hodgson and Jeremy Su'a.
"I've also learnt a great deal from Sam Vesty. We have lots of one-on-one sessions working on my skills.
"That's been very useful for me in developing as a player and hopefully it will give me more opportunities to get on the pitch."