Title-chasing Bidvest Wits have refused to release their wunderkind for the world event from May 20 to June 11.
Although Mahlambi is a stellar player, Senong said he had more than enough capable players to handle the pressure that comes with performing on the world stage.
“All my energy is now focused on the group of players I have with me right now,” Senong said.
The National Under-20 side (Amajita) jetted off to South Korea on Wednesday.
“We have three important games and a very fit team to compete in all of them.
“We must never forget that we have quality players like Grant Magerman, Sibongakonke Mbatha and Luther Singh who are capable of leading the team in our attacking third.
“I am impressed with the quality of players we have in this squad and I believe that they have what it takes to help us achieve our goal.
“But with that said, we’ll never close the door to any talented player who wants and deserves to be part of this squad.
“With regard to players who are not here,” Senong added, “we have our Technical Director, Neil Tovey, who is dealing with the matter.
“We’ll probably get feedback from him later.
“But as far as the coaching staff are concerned, we are focused on getting these players ready to do well in this global event.”
To do that, though, Senong would need to make sure his side produce at least two wins and a draw in one of the toughest groups at this global showpiece.
Amajita are pitted in Group D and will lock horns with Japan on May 21, before taking on Italy (May 24) and Uruguay (May 27) in pursuit of a place in the knockout stages.
That his Under-20 side will be competing against teams who had won their respective continental competitions, while Amajita finished fourth in the CAF Africa Under-20 Cup of Nations campaign in Zambia, is not something Senong is intimidated by.
In fact, the Under-20 coach is pretty confident his team will do well in South Korea.
“Every team there has a chance of doing well in this tournament,” Senong said.
“It all depends on whether you believe in your players or not as well as your style of play.
“We haven’t been at the World Cup for some time now, and that's the case with Japan, who we face in our first group match.
“If we win or draw our first match, that will give us the confidence to do well in our remaining matches.”
Asked how many friendlies they’ve line-up before the tournament kicks off, Senong said: “We've lined up a friendly against Costa Rica. We do not have confirmation of other friendly matches.
“But there are 12 teams also preparing for the tournament , and chances are we’ll get some game time when we arrive in South Korea ahead of our opener.”