Group C leaders Italy dropped points for the first time after they were held to a 1-1 draw by Bulgaria at Stadio Artemio Franchi.
Federico Chiesa gave Roberto Mancini's charges the lead in the 16th minute but Atanas Iliev snatched the equaliser for Bulgaria six minutes before the half-time break to earn them only their second point.
Sweden leapfrogged Spain at the top of Group B after a surprise 2-1 win at Friends Arena.
Carlos Soler got La Roja an early opener in the fourth minute but only for Alexander Isak to find the equaliser for Sweden a minute later.
Viktor Claesson was the hero for Jan Andersson's charges after netting what proved to be the winner just before the hour-mark.
England maintained their perfect record at the top of Group I after a resounding 4-0 victory over Hungary at Puskas Arena.
Hungary managed to restrict the Three Lions to no goals in the first stanza, but once Raheem Sterling broke the deadlock ten minutes from the half-time break, the floodgates opened, as Harry Kane, Harry Maguire and Declan Rice all got on the scoresheet.
Belgium remained unbeaten, with a three-point lead at the top of Group E after annihilating Estonia 5-2 courtesy of a brace by Romelu Lukaku at A. Le Coq Arena.
Estonia gave the Red Devils a scare after Mattias Kait gave them an early lead in the second minute but Hans Vanaken got the equaliser midway through the first stanza and the visitors were back in control, with Lukaku scoring in either half and second-half goals by Axel Witsel and Thomas Foket completed the rout.
Erik Sorga scored what proved to be another consolation goal for the hosts seven minutes before time.
Hansi Flick started his reign in charge of Germany on a winning note after a 2-0 victory over Liechtenstein in Group J at AFG Arena.
Timo Werner broke the deadlock for Die Mannschaft four minutes before the half-time break and Leroy Sane sealed the deal 13 minutes before time, as Germany moved up to within a point of surprise leaders Armenia in second place.
Poland moved up to second in Group I after drubbing Albania 4-1 at PGE Narodowy.
Robert Lewandowski and Adam Buksa scored in the first stanza for Poland before Grzegorz Krychowiak and Karol Linetty secured the three points with goals in the second stanza.
Sokol Cikalleshi scored what proved to be a consolation goal for Albania in the first stanza.