The two recently completed a three-week training session and have decided to extend their collaboration, with Ferrer joining Zverev in the south of France, where the 23-year-old German has been playing exhibitions and training.
"When I was looking a few weeks ago for another member for my team, I kept thinking of David's professionalism, his ability to squeeze a lot from his physique and his game," Zverev told ARD in German. "To take my game to the next level, I preferred someone who has been in the same position."
Ferrer got as high as No. 3 and reached the French Open final before his retirement in 2019.
Zverev is also still coached by Alexander Sr., his father, who has been working with him consistently, including through previous splits with high-profile coaches Juan Carlos Ferrero and Ivan Lendl.
The three-time Masters titlist and former ATP Finals winner says this pairing is off to a good start. Zverev, who has not yet decided whether to play the US Open, has not specified whether Ferrer will accompany him to any hardcourt events but is likely to be in Zverev's box for the clay season.
"It was soon obvious that our goals and personalities fit together," he noted. "I am a player who needs repetition. In this way, David is perfect."
Zverev is No. 7 in the rankings.