Both players are set to line up in the UEFA Champions League final for Liverpool and Tottenham respectively.
Many Newcastle fans may be wondering how such talented players were let go, even if Sissoko did leave for a big fee.
Benitez spoke about the circumstances surrounding both sales with reporters.
Asked if Magpies fans should be surprised those players enjoyed success after leaving, Benitez said to reporters: "I don't think so.
"The fans they know that they are both good players. It depends on the environment, it depends on the moment, it depends on the situation of each player.
"You can't blame anyone, you can't blame the club, you can't blame me, you can't blame anyone because they wanted to go because they had offers - good offers - and they wanted to stay in the Premier League.
"It is not fair for me to talk only about Sissoko but he is in the final and I am really pleased. I am still in contact with him and Gini.
"They were good players for us but we were relegated and they had offers. Sometimes players do not get offers when they are relegated.
"They did and I am telling you Sissoko had three very good ones, including one very important one. That is good for them because you go down and have top sides interested in you.
"Maybe they were not fine here because the team was not doing well. But they have the skill and the pace. You cannot complain or say anything negative about what they did here.
"I'm telling you that three or four other players [had attitude problems]... but I can tell you these two, and I will not name anyone else, but these two were really good professionals from day one until the last minute."