The 25-year-old missed a chunk of last season with a knee problem and was ruled out of the final two games when Royals’ fell agonisingly short of the Championship play-offs.
However, the flamboyant midfielder - third in the club’s Player of the Season awards behind Chris Gunter and winner Jordan Obita - has hinted that further surgery is the only viable option if he is to return for pre-season in tip-top condition.
The injury also ended his hopes of sneaking into Jurgen Klinsmann’s USA World Cup squad, which was announced on Monday.
Hoffenheim signing Williams, who also had a minor op in March, explained: “I try my best to play good football, but unfortunately I was dealing with injuries again and again and again.
“It was so frustrating, especially towards the end of the season when we had so many important games and I couldn’t be involved in the last two.
“Now I just have to focus on getting my knee straight over the summer and come back next season.
“I tried my best to help us get promoted, but I couldn’t do much because of my knee.
“The first thing I must do is get that straight because it’s important to be healthy.
“Then I will recover over the summer, get our minds straight again and try and have another good season.”
Williams took time to settle at the Madejski Stadium following his move from German outfit Hoffenheim last summer.
But he soon progressed and was a regular in Nigel Adkins’ midfield before he was struck down by his knee injury once again.
Williams made 32 appearances in all competitions and scored three goals
during the campaign, and he insists Royals supporters are yet to see the best of him in a hooped shirt.
“The people at Reading trusted me, and when I am fit and healthy I can show that I can be an important player for this club,” he confidently declared.
“Sometimes things go well and sometimes not, because you can’t win all the time.
“I was very happy with my first season with Reading and now I’m looking forward.”
Williams has been linked with a move to the Premier League and Reading could be tempted by a seven-figure offer while chairman Sir John Madejski continues to look for a new owner.
Madejski - whose wealth has plummeted from £400m to around £100m according to reports - needs fresh investment from elsewhere.
However, Williams insisted: “I’m happy here, I have friends here and I live in the area where I work, which is important.
“Everyone wants to play in the Premier League but I didn’t sign a four-year
contract with Reading for no reason. I will just focus now on recovering and try my best to help the team go up next season.”