Victory would take our current run to four wins in the last five in the Premier League in this important festive period after an outstanding performance and 3-0 win at Burnley on Saturday.
Southampton are currently 13th in the Premier League and without a win in six.
"Of course, we are going to play a tough game and we need to keep our momentum, keep going and the three points are so important for us as we keep fighting for the top four," said Mauricio.
Mauricio's former club, the Saints are now managed by his old acquaintance and fellow Argentine Mauricio Pellegrino, who played for Buenos Aires side Club Atletico Velez Sarsfield between 1990-99 and then Barcelona and Valencia in La Liga between 1999-2005.
"This is an important game and of course it means a lot for me because I love the club and the people there," added Mauricio. "It was an amazing year and a half for me and I will always keep those memories in my heart.
"Myself and Mauricio played together when we were very young in Argentina. I know him very well but on Boxing Day, we’ll be enemies!"
Spurs v Saints - Boxing Day information for fans