Charles, 22, struck a 96th-minute winner on Tuesday evening as four second-half goals completed an unlikely comeback against the Foxes.
The Northern Ireland ace was one of three substitutes to score in a second-half display that washed away the first-half errors that left Saints in a hole
Charles, who knew his curling effort would hit the net the moment it left his boot, explained how there was a belief that Saints could turn things around.
“Tonda said that if we score one goal, then it’s right back on. We scored one 15 minutes in, so that helped us push on,” he told the Daily Echo.
Shea Charles (left) and Taylor Harwood-Bellis celebrate their dramatic late win at Leicester. (Image: Joe Giddens/PA)
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“It’s just about being together. Coming in at half-time, you need cool heads, and I feel like we’ve got that. Last time we came here in the Championship, we got beaten 5-0.
“I’m sure a few of the boys were thinking we can’t let that happen. But then to turn it around and go and win the game is unbelievable. Credit to all the boys.”
Saints, at 3-0 down, made three changes at the break. Ross Stewart replaced Cam Archer, Charles came on for Caspar Jander, and Kuryu Matsuki took the place of Tom Fellows.
It was Stewart, a target man rather than a player better suited to running in behind, who sparked the comeback with Southampton’s first goal of the night.
With a big man up front, Saints could hit more crosses into the box, and their first three goals were a result of that. Charles says he felt Stewart’s presence.
“We had Cam in the first half, and then Roscoe came on, and it creates a different challenge for the defenders,” the midfielder explained.
Shea Charles of Southampton celebrates with Ross Stewart after a late, late win at Leicester. (Image: Southampton FC/Matt Watson)
“You can go a whole half with Cam, a smaller, quicker player, and then Roscoe and Cyle come on, and it’s a completely different game for them.
“Making three changes, bring on fresh legs, it’s our job to go in and make a change on the pitch. I feel like we did that.
“We gave a new life, a bit of energy to the team, and it just changed the whole dynamic. In every game, you need different personalities, different types of players.
“It was tough for them, and the type of players we’re bringing on for this league is incredible. There are so many teams that have a chance to go up this year. That’s the Championship.”