Spain and Italy level atop group as are Serbia and IrelandGeorgia's Jaba Kankava, left, battles for a ball with Serbia's Dusan Tadic during the 2018 World Cup qualifying Group D soccer match between Georgia and Serbia at the Boris Paichadze Dinamo Arena in Tbilisi, Georgia, Friday, March 24, 2017. (AP Photo/Shakh Aivazov)
Halfway through European qualifying for the 2018 World Cup, there is little to divide some of the teams.
Spain and Italy continued their tense battle for top spot in their group with comfortable victories on Friday.
The two countries remained tied atop Group G after Spain defeated Israel 4-1 in Gijon, while Italy beat Albania 2-0 in Palermo in a match halted for nearly nine minutes after Albania fans threw flares onto the pitch.
Serbia and Ireland are also level on points at the top of Group D. Serbia won 3-1 at Georgia to move top on goal difference after Ireland was held to a goalless draw by 10-man Wales.
Croatia moved three points clear of Iceland in Group I after beating Ukraine 1-0 for its fourth successive victory.
Only the group winner automatically secures a spot for the World Cup in Russia. The second-place team must go through a playoff to make it to the 2018 tournament.
Here is a look at each European qualifying group in play on Friday:
Italy kept its cool as the flares rained down to ease to a victory over Albania as captain Gianluigi Buffon marked his 1,000th match with a clean sheet.
The match had to be halted in the 57th after Albania fans threw flares onto the pitch.
''I'm upset by the flares thrown by some of our fans,'' Albania's Italian coach Gianni De Biasi said. ''I've been in charge of Albania for five years and I've seen something that's never happened before. I would never have thought I'd see something of the sort.''
The referee had already stopped the match for about a minute in the first half when flares were thrown by the visiting fans after Italy was awarded a penalty that Daniele De Rossi converted in the 12th.
Ciro Immobile doubled Italy's lead in the 71st, heading in Davide Zappacosta's cross from the right flank.
Spain remained above Italy on goal difference after extending its unbeaten streak in World Cup qualifiers to 58 matches.
David Silva and Victor ''Vitolo'' Machin gave Spain a comfortable halftime lead. Diego Costa netted shortly after the break and Francisco ''Isco'' Alarcon sealed the result just before the final whistle after Lior Refaelov had scored a 76th-minute consolation for Israel.
''We've done well against a very difficult team,'' Spain coach Julen Lopetegui said.
Israel is four points behind Spain and Italy, with Albania two points further back.
Second-to-last-place Macedonia earned its first points with a 3-0 win at last-place Liechtenstein.
Serbia fought back from conceding an early goal to jump into the group lead with a comfortable victory against winless Georgia.
Nika Kacharava put the hosts ahead only six minutes into the match, but Dusan Tadic equalized by converting a penalty kick before halftime, then set up second-half goals for Aleksandar Mitrovic and Mijat Gacinovic.
Ireland fell behind Serbia on goal difference despite playing with a man advantage for 20 minutes against Wales.
Neil Taylor was sent off in the 69th minute after a dangerous tackle on Seamus Coleman, who had to be carried off the field with a broken right leg.
''If you look at the last 20 minutes, playing with 10 men, a point is not the worst result,'' Wales forward Gareth Bale said.
Wales is four points below the top two, level with Austria, which beat Moldova 2-0.
Croatia took control of the group with a 1-0 victory over Ukraine as their fans had a first chance to celebrate a victory at the Maksimir Stadium.
It was the first home match Croatia was allowed to play in front of their fans in the campaign. FIFA had ordered the stadium in the capital to be closed to fans when Croatia hosted Turkey and Iceland last year as punishment for previous incidents of racism and disorder.
Nikola Kalinic scored the only goal of the match in the 38th minute to inflict Andriy Shevchenko's first defeat as Ukraine coach.
Ukraine slipped to third, five points below Croatia and level with Turkey, which beat Finland 2-0 thanks to two goals in four minutes from Cenk Tosun.
Iceland moved into second, three below Croatia, with a 2-1 win away to Kosovo.