Hill admitted his disappointment that Sanderson would not join Warriors on the Aviva Premiership quest but insisted there was depth in the squad and new opportunities would open for other players.
"Pat's reputation as a player throughout the game is outstanding and he has been a true leader at Sixways over the years.
"From my perspective, I was delighted last year that he took up the challenge of two up and coming players, in Jake Abbott and Matt Kvesic. It was a really good battle for the starting shirt and Pat proved himself yet again as the fittest person at the club. When you consider what his body has been through, that was an outstanding achievement.
"His motivation to always stay ahead of the rest was superb and when he played in the middle part of the season he produced some of the best rugby I have ever seen him play. His contribution, with and without the ball, was immense.
"It is very disappointing for him to have to end his career through injury, when you look at what he has achieved and done for this club and ahead of our return to the Aviva Premiership.
"However, he was a key part in a great achievement in getting us back to the top-flight last season. Even when he was injured, when it would have been hard for him to watch the play-offs, he was still around the squad and wanted to be involved. That is testament to his passion for the Warriors, which I will know will continue despite this news.
"We already knew that we would be without Pat for the start of the season and signed Sam Betty," added Hill. "Sam now becomes a very important member of the squad and the competition for a place in the back row will be as fierce as ever."