After Bale joined Real Madrid in a big-money deal, Spurs were looking to help fill the void with the two young Croatian stars. Much to Mamic's chagrin, Halilovic had a last-minute change of heart.
"Our biggest failure were transfers of Alen Halilovic and Tin Jedvaj," Mamic told Arena.
"When they were 16, Tottenham sold Bale to Real for €100m and wanted to buy them for €25m. I met [Tottenham chairman] Daniel Levy in London.
"We started negotiations at €10m and finished at 25, and signed a deal. As I returned to Zagreb, I presented that deal to the Halilovic and Jedvaj families and they agreed.
"But after a few days, Halilovic's father changed his mind saying Alen was not happy with the deal. I went crazy and called the whole thing off. And Dinamo lost because we sold them a couple of years later for much less money."
Halilovic was eventually sold to Barcelona two years later but didn't made an impact in Catalonia and was sold to Hamburg, though Barca does retain a buy-back clause. He is currently is on loan at La Liga side Las Palmas.
The negotiations between Mamic and Levy weren't the first time the two sides held talks over players. In 2008, one transfer between Dinamo and Tottenham went through in a much more successful fashion.
"When we negotiated with Tottenham over [Luka] Modric, Levy offered €10m in cash," Mamic recalled, before saying he returned Spurs' offer with a strong refusal accompanied by a Croatian swear word.
"They understood and accepted a €25m deal," Mamic said.