Both teams will be seeking an advantage ahead of next week's return, after which the winners will advance to a second-stage encounter with either Bodo/Glimt or KI; the losers being consigned to the Europa Conference League.
Only a few weeks after sealing a domestic double with victory in May's Welsh Cup final, The New Saints were back in training for their latest crack at the Champions League - a competition in which they have never before reached the group stage.
The Saints have reached the third qualifying round of either the Europa League or Europa Conference League in three of the last four years, so certainly start with some hope of causing an upset or two this season.
After making it two wins from two in their opening pair of pre-season friendlies - a 5-1 victory over last season's Cymru Premier runners-up Bala Town and a 2-1 success against Cliftonville - the Oswestry outfit were beaten 2-0 by Larne last Wednesday, in their final warm-up game.
Head coach Anthony Limbrick has already accrued experience of continental competition, as during the inaugural season of the Conference League, his side progressed through the first two qualifying rounds: beating Glentoran and FK Kauno Zalgiris. Penalty shootout heartbreak was to follow in the third round, though, against Czech club Viktoria Plzen.
Limbrick soon lifted his squad's spirits and ultimately became the first Australian manager to win a European top-flight title, and now the Welsh champions' first qualifying tie of the new campaign pits them against Irish opposition for the second season on the spin.
While TNS strolled to the Cymru Premier trophy by a 21-point margin, this year's first round opponents secured the NIFL Premiership by a single point, just ahead of Cliftonville.
Manager David Healy, once a renowned Northern Ireland international with 95 caps and 36 goals to his name, has now led the Blues to five titles in the last six seasons, and the latest was the 56th time they have been crowned national champions.
In preparation for their opening Champions League tie - which concludes next week, back at Windsor Park - Linfield faced the Qatar national team in their first pre-season outing, and got the better of this winter's World Cup hosts with a 1-0 victory in Marbella.
Having returned home after a week-long training camp in Spain, Healy's men then followed a goalless draw against Newtown with a 2-1 defeat to SPFL side St. Mirren, despite loanee Daniel Finlayson - who only recently completed his switch from Saturday's opponents - levelling the game after 19 minutes.
Attention now turns to competitive action on Tuesday night, when the South Belfast side meet opposition they have played three times before over the course of the past 15 years.
After a 2-1 win for Linfield in 2007, pre-season fixtures in both 2009 and 2010 finished all-square, but the stakes will be far higher when the teams meet twice over the next few days.
Two summer signings are in contention to start for The New Saints on Tuesday night, as winger Josh Daniels - a former Republic of Ireland Under-21 international - joins goalkeeper Daniel Atherton in Anthony Limbrick's squad.
The latter, a graduate of Liverpool's academy, has previous experience of the UEFA Youth League, and he will compete with Connor Roberts to feature as the hosts' last line of defence.
Scottish striker Declan McManus is set to lead the line up front, having been named the 2021-22 Cymru Premier 'Player of the Season', with a total of 24 league goals.
Linfield, though, have lost their main man in attack, as Christy Manzinga recently left for Hungarian club Zalaegerszegi, after finishing last season as the club's top scorer with 20 goals from 37 appearances.
In his absence, there should be a first competitive outing for striker Robbie McDaid, who arrived at the club from rivals Glentoran last week and played for his former club against TNS at this stage last season.
Finnish forward Eetu Vertainen has not been registered in time to play this week, but other new signings, such as Chris McKee, Joel Cooper and Daniel Finlayson - the latter, a Northern Ireland Under-21 international, who joins on loan from St Mirren - should play a part.
The New Saints possible starting lineup:
Roberts; D. Davies, Astles, K. Davies, Marriott; Routledge, Brobbel, Redmond; Daniels, McManus, Cieslewicz
Linfield possible starting lineup:
Johns; Finlayson, Roscoe, Hall, Shields; McClean, Mulgrew; Fallon, Cooper, Fallon; McDaid
We say: The New Saints 1-1 Linfield
Neither side is likely to give too much away in the first leg of this tie, so it could be a close-fought affair at Park Hall.
Nonetheless, the visitors possess enough attacking threat to strike at least once - setting themselves up well for the return in Belfast next Wednesday.
For data analysis of the most likely results, scorelines and more for this match please click here.
body check tags ::
Previews by email