After edging out group minnows Andorra, the Swiss now return home to Lucerne, where they will aim to extend their advantage over the visitors to five points.
Match preview
Switzerland may have made it three wins from their first three fixtures when they visited Andorra on Friday night, but their inability to finish off the tiny principality certainly caused some concern for their fans.
The road to European Championship qualification is expected to be straightforward for a nation regularly found in the knockout stages of major finals, but after the Nati's two-goal advantage was unexpectedly halved at Estadi National midway through the second half, they ultimately had to settle for a 2-1 victory.
Nonetheless, Murat Yakin's men had already beaten Belarus and Israel in their first two games to reach the summit of Group I, and with the top two finishers guaranteed a place in Germany next summer, they are odds-on favourites to qualify.
With 10 goals racked up so far - albeit against relatively modest opposition - Switzerland now tackle their nearest rivals for first place, before returning to action away to Kosovo in September.
After making the quarter-finals of Euro 2020 and the last-16 five years earlier in France - plus progressing from the group phase of the last three World Cups - the Swiss public are expectant, even if their team missed out on this year's UEFA Nations League finals.
Therefore, victory by Lake Lucerne will be on the agenda to conclude a long, hard season by cementing top spot in Group I.
Having taken care of business against Andorra and Belarus in the March international period, Romania came up short in their third Euro 2024 qualifier on Friday, when they failed to break down Kosovo in Pristina.
Coming into their summer camp on a run of four wins from five matches, the Tricolorii targeted another success to pull clear of the pack alongside Switzerland, but they were ultimately held goalless by a Kosovan team that remains unbeaten in the group.
Even so, Romania's only defeat since the start of the 2022-23 season came in a friendly against Slovenia, though they could not do enough to overcome a slow start and avoid relegation to the third tier of the Nations League.
After making a more promising start in European Championship qualifying, Edward Iordanescu's side now face probably their toughest test of the campaign, away to the clear group favourites.
However, even taking a point would keep them ahead of third-placed Israel, who are expected to turn over Andorra in Jerusalem, and ending an eight-year absence from major finals could then be on the cards heading into September's double-header on home soil.
Switzerland Euro Champ Qualifying form:
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Switzerland form (all competitions):
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Romania Euro Champ Qualifying form:
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Romania form (all competitions):
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Team News
In the absence of Breel Embolo - who has been struggling with a knee problem for several months - Basel forward Zeki Amdouni should again start for Switzerland, having taken his tally to three goals from four senior appearances on Friday night.
A strong starting XI failed to sweep aside Andorra in the manner expected, so Murat Yakin could make some changes to his side on Monday, with Haris Seferovic and Fabian Schar perhaps the strongest contenders for promotion from the bench.
As ever, experience is plentiful within the Nati this week, as captain Granit Xhaka, Torino defender Ricardo Rodriguez and 113-cap forward Xherdan Shaqiri all feature in a familiar squad.
Romania's attempts to freshen up the national team will see a younger group travel to Lausanne, though 30-year-old midfielder Nicolae Stanciu - now based in China - will skipper the side.
First-choice goalkeeper Ionut Radu is unavailable after suffering an injury on the final day of Ligue 1, when his loan club Auxerre were relegated. He has undergone surgery before returning to Inter Milan, so Horatiu Moldovan should start in Switzerland.
Ianis Hagi was called up for the first time in two years following an injury-plagued spell in Glasgow, but may again be consigned to the bench; either George Puscas or Denis Alibec will lead a likely front three for the visitors.
Switzerland possible starting lineup:
Sommer; Lotomba, Akanji, Schar, Rodriguez; Freuler, Zakaria, Xhaka; Amdouni, Seferovic, Vargas
Romania possible starting lineup:
Moldovan; Manea, Dragusin, Burca, Oprut; Marin, Baluta, Stanciu; Morutan, Puscas, Man