Second-half goals from Danny Drinkwater and Jamie Vardy saw Leicester come from behind to beat Middlesbrough in their Championship opener.
Lukas Jutkiewicz gave the hosts a 35th-minute lead as the ball went into the net following a challenge between him and ex-Boro defender Sean St Ledger.
Drinkwater's fierce 20-yard drive restored parity though on the hour mark.
And Vardy's neat finish won the match seven minutes later.
Looking to respond to last season's play-off semi final defeat by Watford, Leicester started slowly against their hosts with Middlesbrough dominating the opening 45 minutes.
Jutkiewicz's opener was the least they deserved although there is some argument about whether he or St Ledger got the final touch to Mustapha Carayol's cross.
Striker Jutkiewicz and winger Carayol then saw shots saved by Kasper Schmeichel, with Grant Leadbitter also denied by the busy Leicester goalkeeper late in the half.
It was a different story after the break as the Foxes started to take control of the match.
And after a strong spell of pressure Leicester levelled on the hour with Drinkwater shooting powerfully into the net.
The match had completely turned around seven minutes later as David Nugent peeled to the left and slotted a neat ball forward for Vardy to race clear of Williams and get into the box before lifting it past the advancing Jason Steele.
Leicester could have secured a more emphatic win before the end with Nugent and Vardy denied by Steele late on.
Middlesbrough manager Tony Mowbray:
"We played really well in the first half. We had a good shape, passed the ball around well, created chances and made good decisions in key areas.
"But Leicester are a good side. They came back at us in the second half; we stopped doing the basics well and let them back into the game.
"The bottom line is you have to take your chances. We said it so many times last season that you have to close out games when you are are on top."
Leicester manager Nigel Pearson:
"In the first half we didn't work hard enough, we didn't make enough positive decisions and we let Middlesbrough shape the game.
"But in the second half we made a few more positive decisions, worked harder and got our reward. We scored two very good goals, could have had a few more and possibly should have had a penalty.
"We were well worth the win, although it looked a bit precarious at half-time."