Van der Hart was one of Heerenveen's two often-used goalkeepers, with former Dutch World Cup stopper Andries Noppert being the other. Dutch icon Robin van Persie took over as Heerenveen boss prior to last season, but on-field controversies chased the former striker: Heerenveen were inconsistent, were eliminated from the KNVB Beker by amateur side Quick Boys, and lost 9-1 to AZ.
Van Persie seemingly blamed his goalkeepers. Van der Hart was dropped twice in favour of Noppert, once during the 3-2 cup loss against Quick Boys when Heerenveen were leading 2-1. Van Persie explained it had to do with high crosses, which Noppert was better at.
In a conversation with Omrop Fryslan, Van der Hart was asked whether Van Persie knows anything about goalkeepers. The former Ajax stopper answered shortly: "No."
Noppert caused a penalty less than two minutes after coming on, and Van der Hart saw his side lose 3-2 in extra time. The latter didn't buy Van Persie's explanation: "I thought it was a forced moment," he said.
"We were in control of that game after the 2-1. If that substitution had not happened, we would have gone ahead. That was just a tactical blunder. Although he won't admit that himself."
Heerenveen's 9-1 loss away at AZ in September was the club's biggest Eredivisie loss in history. Van Persie implemented a heavily attacking playstyle at Heerenveen, which didn't work out against AZ. Nevertheless, Van Persie refused to step away from the tactic during the game.
"With that playstyle comes the risk of falling flat on your face," Van der Hart said during the Sportcast podcast. "When you go down 4-1 during a game like that, you know you won't win anymore. It might turn 5-1, but you might lose 5-1 once in a while away at AZ.
"But now, it was like we were a youth team being commanded to go on with what had been going wrong all game long. That was the message. I think he thought too much like a youth coach in development."
Robin van Persie left sc Heerenveen in February to succeed Brian Priske at Feyenoord.