Pochettino fielded three 18-year-olds in his starting line-up - Luke Shaw, Calum Chambers and James Ward-Prowse - and it was Shaw who earned the penalty that Rickie Lambert dispatched in the 90th minute.
The Argentinian also fielded new signings Victor Wanyama and Dejan Lovren, players he felt would add to their competitive edge, and he has not ruled out more arrivals before the transfer window closes.
Of his young trio, Pochettino said: "All I can say is that I am confident they are good enough players to play in this league.
"I am only taking advantage of the work that has been in place already at Southampton for the last four years - the amazing work that (executive chairman) Nicola Cortese has done in that sense, in bringing young players through the academy system.
"The new signings have come in to improve the team where I thought it needed improving, in our defence and the midfield.
"As opposed to last season, we are a much more competitive team now with these two new signings.
"We are still looking in these last two weeks of the transfer window, and we'll see what happens."