The home side got points on board with a stunning 4-2 win over Wales in Cardiff on Friday, while Latvia lost an exciting game against Turkey at the death.
Match preview
Armenia versus Wales was not expected to be a six-goal thriller due to the home side's tendency to keep things tight in Cardiff.
However, Oleksandr Petrakov's side ended the Welsh's 12-game unbeaten home run in European Championship qualifying — nine wins and three draws — since a defeat by England in 2011.
Grant-Leon Ranos and Lucas Zelarayan scored two each in Havakakan's victory that ended Armenia's sequence of four consecutive losses in Euro qualifying.
Petrakov's team could consolidate on that triumph when they host Latvia, and maximum points could take them into second place with Wales and Turkey facing off in Group D's other game.
Croatia's participation in the Nations League decider opens the door for Armenia to leapfrog the group favourites, although the latter will have played a game more.
Opponents on Monday are Latvia, whose late 3-2 defeat by Turkey sees them rooted to the bottom of the section.
Kristers Tobers thought his 94th-minute equaliser had secured a point in Riga, only for Irfan Can Kahveci to score a minute later for the visitors.
The defeat was the successive home game against the same opponent that had produced a late winning goal for the Turks — Burak Yilmaz scored a 99th-minute penalty in a World Cup qualifier in October 2021 — but Friday's was a kick in the teeth.
Latvia are yet to secure a point after two games, with the latest defeat leaving Dainis Kazakevics's team without a point from six available.
The 3-2 loss means the Baltic nation have lost 12 of their last 13 in Euro qualifying, offering little optimism for Monday's encounter in Yerevan.
Armenia Euro Champ Qualifying form:
L
W
Armenia form (all competitions):
L
D
L
L
D
W
Latvia Euro Champ Qualifying form:
L
L
Latvia form (all competitions):
D
W
L
L
L
L
Team News
Zelarayan and Ranos were first-rate against Wales, and the pair are anticipated to play from the off against Latvia.
Andre Calisir was withdrawn after an hour in Cardiff, and Monday's game may come too soon for the Armenia defender.
Eduards Emsis levelled for Latvia against Turkey but was dismissed after receiving a second yellow, ruling out the suspended midfielder for their trip to Yerevan.
Nils Purins replaced Pavels Steinbors between the sticks in Friday's defeat, and it remains to be seen if the first-choice goalkeeper returns for next week's clash.
Armenia possible starting lineup:
Cancarevic; Haroyan, Harutyunyan, Mkrtchyan; Dashyan, Iwu, Spertsyan, Tizniyan; Briasco, Zelarayan; Ranos
Latvia possible starting lineup:
Purins; Savalnieks, Oss, Balodis, Jurkovskis; Tobers, Saveljevs; Jaunzems, Uldrikis, Ciganiks; Gutkovskis