Having suffered a thigh injury at the 2016 European Championship, Germany international centre-back Boateng only made his first appearance of the season for his club in September.
However, the 28-year-old struggled for fitness throughout the campaign and made just 21 competitive appearances.
“The season was anything but nice and successful for me,” Boateng told Sky. “It was difficult because at no time was I at 100 percent fitness.”
After returning from his muscle injury, Boateng played seven Bundesliga games before a shoulder injury ruled him out again.
“That injury completely got me out of my rhythm, and I had to return to fitness for the Champions League matches,” he said.
“These days, you get less and less time to return to 100 percent.”
In the final match of the season, Boateng suffered a muscle injury in his right thigh, but said: “As things stand now, I will be ready when it all kicks off again on July 1.”