Premier League high-flyers Everton were knocked out of the EFL Cup by Championship side Norwich, who battled to a 2-0 win at Goodison Park.
Ronald Koeman's team are unbeaten in the Premier League, to sit second in the table, following a run of four straight wins.
However, the Toffees came unstuck when former frontman Steven Naismith, who left for Carrow Road during the January transfer window, put the Canaries ahead four minutes before the break when he scooped the ball into the top-left corner.
When Josh Murphy cracked in an angled drive off the underside of the crossbar on 74 minutes, there was no way back as Alex Neil's men - second in the Championship table - secured their place in the fourth-round draw.
There was no shock at the City Ground, where a young Arsenal side saw off Nottingham Forest 4-0, with two goals for new signing Lucas Perez.
The Gunners, who made the expected sweeping changes from their 4-1 Premier League win at Hull, went ahead on 23 minutes with a long-range shot from £35million Swiss midfielder Granit Xhaka.
Perez, who joined Arsenal from Deportivo La Coruna, netted a penalty on the hour and then added a third goal with a fine individual effort on 71 minutes.
Alex Oxlade-Chamberlain scored a fourth for the visitors in stoppage time.
Liverpool also avoided an upset away at Championship opposition as they beat Derby 3-0.
Defender Ragnar Klavan put the Reds ahead on 24 minutes, with two goals in the space of five minutes during the second half seeing Liverpool take control of the tie.
Phillippe Coutinho slotted home in the 50th minute, before Divock Origi added a third on 54 minutes after being played into the Rams' box by the Brazilian.
Reading had a man sent off, but went on to win 2-1 at Brighton.
Jaap Stam's side took the lead on 32 minutes through a close-range volley from Republic of Ireland international Stephen Quinn, but had defender Tyler Blackett dismissed just before half-time following a late challenge on Sebastien Pocognoli.
The Royals, though, found themselves 2-0 up early in the second half when midfielder John Swift, who signed in the summer from Chelsea, netted his second goal in three days on 54 minutes.
Brighton reduced the deficit through Tomer Hemed with five minutes left, but could not conjure an equaliser to force extra-time.
Newcastle avenged their Championship defeat to Wolves at the weekend with a 2-0 win over the Black Country club.
The Magpies - beaten 2-0 at home by Walter Zenga's side on Saturday - had the St James' Park faithful on their feet when Matt Ritchie slotted them in front on 29 minutes, and it was quickly 2-0 when Yoan Gouffran volleyed in.
At Elland Road, Leeds beat Blackburn 1-0 with a late goal from Chris Wood, who bundled the ball in on 85 minutes after his header had been saved.
Preston striker Simon Makienok scored a hat-trick to send Premier League side Bournemouth crashing out 3-2 after extra time at Dean Court.
Makienok had given North End and early lead after just 10 minutes. Bournemouth were level eight minutes into the second half when Lewis Grabban scored from the penalty spot, and Dan Gosling nudged the hosts ahead after 76 minutes when he netted from close range.
However, Simon Grayson's visitors from the Championship fought back to equalise with five minutes left when Makienok glanced in a header. The Dane then won it for Preston after 111 minutes when he stabbed the ball over goalkeeper Adam Federici.
Chelsea recovered from two goals down to beat 10-man Leicester 4-2 at the King Power Stadium.
After Blues forward Pedro had seen an early effort ruled out for a tight offside call, Premier League champions Leicester went ahead after 17 minutes through Shinji Okazaki's header.
The Japan forward added a second scuffed effort after 34 minutes, but Chelsea puled a goal back just before half-time through Gary Cahill.
Chelsea were level four minutes into the second half when full-back Cesar Azpilicueta cracked in a fine 20-yard volley.
Leicester went into extra time with 10 men after defender Marcin Wasilewski collected a second yellow card for clashing with Diego Costa.
Chelsea got themselves in front for the first time as midfielder Cesc Fabregas scored after being set up by Eden Hazard just two minutes into the first period of extra-time. The Blues struck again on 94 minutes, with Fabregas lashing the ball into the roof of the net.