Leicester started their pre-season campaign with a 2-1 victory over Oxford United at the Kassam Stadium on Tuesday.
The Premier League champions named a strong starting line-up that included Riyad Mahrez, Robert Huth, Danny Drinkwater and Wes Morgan, whose new contract was announced shortly before kick-off.
With N'Golo Kante sold to Chelsea, Hamza Choudhury started in central midfield along with Drinkwater.
It was League One newcomers Oxford who took the lead after 13 minutes, though, when Chris Maguire's free-kick beat the dive of Kasper Schmeichel.
Demarai Gray and Choudhury were the Foxes' standout players of the first half and it was Gray who scored the equaliser in the 28th minute, firing home from just inside the box.
Record signing Ahmed Musa was introduced at the break along with fellow summer signings Luis Hernandez and Ron-Robert Zieler.
The Foxes dominated the second half and substitute Jeffrey Schlupp secured victory when he drilled in a low shot on 69 minutes.
West Ham conceded two late goals to draw 2-2 with FC Slovacko in Austria.
Mark Noble gave the Hammers the lead with a fine strike from the edge of the box in the 37th minute.
Half-time substitute Ashley Fletcher headed home a second shortly after the break from youngster Domingos Quina's cross.
But Czech side Slovacko took advantage of several West Ham changes to score twice in the final five minutes through Eldar Civic.
Meanwhile, goals from Etienne Capoue, Troy Deeney and Steven Berghuis handed Watford a 3-1 victory over Union Berlin in Austria.
Capoue put Watford ahead early in the first half, getting on the end of an Odion Ighalo cross to score his second goal in two pre-season games.
Just before the break, Abdoulaye Doucoure was brought down in the box, with captain Deeney stepping up from the spot to extend Watford's lead.
After a host of second-half changes, Bundesliga 2 side Union Berlin pulled one back thanks to Maximilian Thiel, but Berghuis netted late on to secure victory for the Hornets
Jarrod Bowen's second-half goal was enough for Hull as they beat Mansfield at the One Call Stadium.
Following a goalless first half, Bowen fired past Brian Jensen after a neat through ball from Shaun Maloney.
Peter Odemwingie came closest to a second for the Tigers, but his effort struck the post with under 10 minutes to go.
An Andre Gray strike salvaged a draw for Burnley following Rhys Turner's opener for Morecambe at the Globe Arena.
Turner netted after Burnley goalkeeper Paul Robinson spilled a cross, but Gray responded with a low strike 11 minutes later in the second half.
In Spain, goals from Dani and Ruben Castro earned Real Betis victory over Middlesbrough at the Marbella Stadium.
Dani slid the ball past Dimitrios Konstantopoulos midway through the first half, with David Nugent striking the post just five minutes later as Boro searched for an immediate reply.
Castro put Betis further ahead after the break, but the two-goal lead was short lived as Jordan Rhodes headed in a minute later.
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