King started in midfield for Leicester and he put in an energetic display, as the two teams played out a pulsating 2-2 draw.
The Welsh international is no longer part of Leicester’s first choice midfield pairing, but Shearer was very impressed by his performance on Sunday.
“I thought King was Man of the Match, I thought he was superb for Leicester,” the former Newcastle United striker said.
“We’ve already mentioned Gray and King [who I thought were good too].”
Leicester named a much changed line up against Spurs, but they came within touching distance of making it into the fourth round.
Tottenham had taken the lead when Christian Eriksen slotted home in the first few minutes, but the Foxes responded well.
Leicester grabbed an equaliser when Marcin Wasielewski powered home a header, and they then took the lead when Shinji Okazaki scored soon after half time.
Ranieri’s side then managed to hold on to their lead until the final minute of normal time, when Harry Kane slammed home a penalty to send the tie to a replay.
Tottenham and Leicester will meet again in Premier League action on Wednesday.