Mauricio Pochettino has claimed his “big risk” of playing Eric Dier in midfield has paid off with the biggest reward of his Tottenham reign.
The England star scored on his debut at West Ham's old Upton Park home in August 2014 — which was the last time Spurs won at the Hammers.
The former Sporting Lisbon trainee signed as a centre-back, but is now an England regular in a midfield role and Jose Mourinho tried to sign him for Manchester United this summer.
Before heading to the London Stadium as the two local rivals meet again in Saturday's lunchtime kickoff, Pochettino said: “I think we feel very proud about him.
“When we signed him, more than three years ago, I think it was maybe our first signing when we arrived at Tottenham.
“At West Ham [that day in 2014], he played as a centre-back with Younes Kaboul and [then] Kyle Naughton was sent off and and Dier played like a full-back and he scored at the end.
“When we signed Toby Alderweireld, we took a big risk not signing another midfielder to give the possibility to Eric to fit into that position on the pitch and it was fantastic.
“Our decision to be brave paid off. In football you must take risks if you want to win.”
The club-record signing of Ajax centre-back Davinson Sanchez this summer is set to limit Dier’s defensive duties but Pochettino insisted he “cannot see negatives” in the 23-year-old’s versatility.
“If he, in time, shows he is great or one of the best in the world in one position, that is fantastic for him,” he said. “But if you can play very well in different positions, there are more possibilities for him to play.”
Pochettino wants Dier to win help win the fight away to their “enemy” West Ham.
Spurs have lost on their last two visits to the Hammers, including the 1-0 in May that ended their title hopes — a worse record than they have away to bigger guns Arsenal and Chelsea.
“It is a derby,” said the former Argentina defender. “It is our enemy — our sporting enemy.
“We will try to be ready to compete, fight and be aggressive.
“For all the excitement and desire they show to beat us, we must show the same. We must show the same desire, excitement and aggressivity.”