France and Australia have the advantage in the 2017 Davis Cup semi-finals after wins for both countries in the doubles on Saturday.
Pierre Hugues Herbert and Nicolas Mahut put France 2-1 up against Serbia with a comfortable win over Filip Krajinovic and Nenad Zimonjic.
Australia then followed suit, with John Peers and Jordan Thompson seeing off Belgium's Rubens Bemelmans and Arthur de Greef in Brussels to also move 2-1 ahead.
Belgium 1-2 Australia
France 2-1 Serbia
Mahut and Herbert put in a dominant performance for France, winning 6-1, 6-2, 7-6 at the Pierre Mauroy Stadium, with the match played under a closed roof due to a poor weather forecast.
France's two-time Grand Slam doubles champions cruised through the opening two sets, although not everything went their way, as shown by the official Davis Cup Twitter account:
After taking the opening set for the loss of just one game, Mahut and Herbert then took an early break in the second to send them well on the way to victory, as shown by We Are Tennis:
France did suffer something of a scare in the third set when Serbia won four games in a row to lead 6-5 and give the watching French team some nervous moments, as highlighted by Live Tennis:
However, the duo eased through in the tiebreak and are now closing in on an 18th Davis Cup final for France.
France just need one more victory to clinch victory on Sunday, with Jo-Wilfried Tsonga taking on Dusan Lajovic in the first of the reverse singles before Lucas Pouille faces Laslo Djere.
Australia will also be favourites to secure a final spot as they edged ahead with a comfortable doubles victory over Belgium.
Peers and Thompson powered past Bemelmans and De Greef, 6-3, 6-4, 6-0, which sparked big celebrations from their supporters, as noted by the Davis Cup:
It was a dominant performance by the Australian duo, with Peers in particular showcasing his talent, according to Live Tennis:
Australia now have their first final in 14 years in sight, with Nick Kyrgios set to take on David Goffin on Sunday before John Millman faces Steve Darcis.
Kyrgios came from behind to beat Darcis in a thrilling five-set match on Friday, and with a Davis Cup record of seven wins in eight matches, he has the form to secure Australia a spot in the final.