Tassotti, who has been Milan assistant under three separate managers since 2001, was placed in temporary charge for Wednesday's Coppa Italia clash following Massimiliano Allegri's sacking on Monday.
Seedorf arrived midway through the match to adulation from the stands, but Tassotti - who has already backed the former midfielder to succeed in the role - stopped short of passing judgement in the aftermath of his fixture in charge.
He told Rai Sport: "Clarence only just stopped playing a couple of days ago, so some might say he has no experience as a coach.
"While others will point out he has played at the highest level for so long that he knows everything he needs to."
Seedorf is expected to be confirmed as coach ahead of Sunday's Serie A clash with Verona, while Tassotti's continued role at San Siro is yet to be defined.
The 53-year-old was happy with the performance of the team against Spezia though, hailing their response to their 4-3 reverse at Sassuolo on Sunday, which leaves them 11th in Serie A.
"It was a good game with some good moves," he added.
"It was delicate due to the moment we are in. Spezia are in Serie B, but a good side and we did well.
"Milan are a little bit in difficulty, but we knew that otherwise this would've happened in June.
"We have the opportunity to improve the situation and the Coppa Italia is a valuable option for Milan to get back into Europe."
