LIVERPOOL, England — Jurgen Klopp did not introduce his Liverpool players to the woman who would subtly change their lives right away. When she joined the team, at the club’s preseason camp in Palo Alto, Calif., last summer, Klopp waited a couple of days, eager to see if her actions would win them over more easily than his words.

“Usually, in preseason, the players eat as much as they can, as fast as they can,” Klopp said in an interview this month at Liverpool’s Melwood training base. He wanted them to slow down, not to “come, eat, go,” to leave their phones outside, to relax.

After a couple of days in Palo Alto, he noticed something was different. The players, aching from his demanding conditioning sessions, were lingering at their tables. They were lining up by the salad bar, intrigued by the choices. “I had not seen that atmosphere before,” he said. “They were staying to eat, and they loved it.”

Only then did Klopp stand up in the restaurant and formally welcome his two new staff members. The first, Andreas Kornmayer, a former fitness coach at Bayern Munich, was easy. “A lot of them knew Andy,” Klopp said. “And they are used to having a fitness coach: He is the drill sergeant guy, shouting at them to run more.”