Atletico Tucuman would move above Union in the Argentine Primera Division table should they claim all three points on Saturday.
The visitors, meanwhile, could climb up to five places by returning to Santa Fe with a victory.
Match preview
Having finished fifth in the regular season last time out, Tucuman will be hugely disappointed to find themselves fifth from bottom after 21 games of the current campaign.
Lucas Pusineri's side have struggled for consistency all season, averaging one-point-per-game ahead of their test against Union this weekend, with only one win from 11 games on the road hardly helping their cause.
However, having recorded back-to-back home victories in recent weeks, Pusineri and his players should have renewed confidence of climbing the table with some more positive results at Estadio Monumental Jose Fierro in the coming weeks.
That said, El Decano were distinctly second best when falling to a 4-1 defeat away to Sarmiento earlier this week, so Pusineri has some work to do in order to rebuild his side's confidence.
Union, meanwhile, have been one of the most improved sides in the division in recent weeks, with Sebastian Mendez enjoying a hugely successful spell at the club prior to his departure earlier this week.
The 45-year-old, who was only appointed as head coach in April, helped his team claim 14 points from an unbeaten run of six matches prior to being poached by his boyhood club Velez Sarsfield.
Union fans should not begrudge Mendez for jumping ship given that he made 177 league appearances for Velez after coming through their academy system as a player, although he will have much work to do given that his new team have lost four matches in a row and sit five points behind Union towards the bottom of the table.
Equally, Tatengue find themselves travelling to Tucuman without a permanent manager in place, and it remains to be seen whether their players are capable of performing without Mendez's guidance given their disastrous form prior to the two-time Argentina international's appointment.
Team News
Tucuman appear likely to remain without Lucas Naranjo, Ruiz Rodriguez and Cristian Menendez due to injury, but Marcelo Ortiz recovered from a knee injury to be named on the bench earlier this week.
The 29-year-old was an unused substitute during his side's damaging defeat to Sarmiento, but Pusineri may look to integrate him back into first-team action at some stage given his undoubted talent.
Union, meanwhile, will travel without Daniel Juarez due to an ongoing knee issue, with the winger unlikely to return until at least August.
They are unlikely to make any alterations to the starting XI that impressively dispatched Independiente by three goals to nil last weekend, with Imanol Machuca set to lead the line once more after bagging during the victory.
Atletico Tucuman possible starting lineup:
Marchiori; Tesuri, Bianchi, Romero, Orihuela; Guille, Sanchez, Acosta, Pereyra; Estigarribia, Coronel
Union possible starting lineup:
Moyano; Vera, Paz, Calderon, Corvalan, Zenon; Roldan, Gordillo, Luna; Domina, Machuca
We say: Atletico Tucuman 2-1 Union
Despite Union clearly being in better form ahead of this huge clash towards the bottom of the table, they may have been rocked by the departure of their manager earlier this week.
Tucuman have won their last two home matches and will therefore feel confident of piling on the misery for their opponents, so we are predicting a narrow win for the hosts.
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