Manchester United won at Sheriff Tiraspol thanks to the first goal of the career of Portugal's talismanic player.
In their Group E opener, the men suffered a defeat at Old United but bounced back with a three point win in Moldova.
Jadon Sancho's cool finish from Christian Eriksen's reverse pass gave the Red Devil's a 2-0 lead at the half.
After being left out of the England squad, Sancho came close to a second but his low shot was cleared off the line by the Sheriff captain.
The first goal of the game was scored by United after Patrick Kpozo tripped Diogo Dalot.
Sheriff could not force David de Gea into any meaningful saves because he did not have the strength to do so from the other side.
Real Sociedad won their second game in a row with a 2-1 victory over Omonia Nicosia.
United's revival following a poor start to the season was brought to a halt at home by Real Sociedad last week, but the side got back to winning ways.
Portuguese starRonaldo played a key part in the triumph, having requested to leave Old United during the transfer window, but ended up staying as no club came in for his services
He had not scored in his previous eight games for United, but he looked like he was about to get one when he shot over the bar.
He did get off the mark of the campaign by slotting in a spot-kick - which was the 699th club goal of his career - but will not get the chance to add to that until after the Manchester City game.
After the international break, Ten Hag's squad will have to play 13 games in 43 days in order to get ready for the World Cup.
The game was being played in Chisinau for security reasons, but the visitors scored their first attack on the contest.
His World Cup place is in serious doubt after he failed to make the Three Lions squad for the upcoming games against Italy and Germany.
He sent the manager a reminder of his abilities by turning a defender and calmly converting his third goal of the season and should have had another, but for his last gasp intercept.
Bruno Fernandes' first-time strike was straight at Maksym Koval as United could not add to their tally.
One of the biggest shocks in European football history took place last season when Sheriff defeated Real Madrid in the group stage of the playoffs.
Many of that squad have left, including the manager, who left the club earlier this year to join the Ukrainian army.
The side are six points clear at the top of the table in their domestic league but their challenge petered out after a bright start against United.
Iyayi Atiemwen twice came close, a strike from range bouncing just wide as well as a free- kick narrowly over.