On Monday, Nick Wagoner of ESPN.com provided comments from both superstars about their friendship, with Sherman saying the five-time NBA champion was "essential" during his rehab process.
"He and I had a previous relationship and talked and texted all the time," the former Seattle Seahawks corner said. "So he gave me some pointers and things I needed to do early on in the process to make sure that I expedited the healing process and I was more proactive than reactive. I think that was one of the big things."
Kobe, who suffered an Achilles injury of his own in 2013, said he tried to keep things lighthearted when he first reached out to Sherman after the setback.
"When I first called to check on him I said, 'Are you all right—I want to make sure you are not being a baby about it?'" Bryant told Wagoner.
Sherman agreed to join the 49ers less than 24 hours after the Hawks released him in March.
The 30-year-old Stanford product owns an impressive resume that includes four Pro Bowl selections, three first-team All-Pro nods and a Super Bowl championship.
"This is the ultimate challenge," he said. "I wouldn't wish this on my worst enemy. It's horrible."
Bryant added Sherman's "mentality is what separates him" and that it makes the 18-time NBA All-Star "excited for him to come back and show the world what he's got."
The longtime shutdown corner and the 49ers kick off the regular season with a road game Sunday against the Minnesota Vikings at U.S. Bank Stadium.