Thanks to a last-minute goal, the visitors arrive with a slender 3-2 lead to defend with everything still to play for between the two Argentinian outfits.
Match preview
Talleres began their Copa Libertadores campaign in impressive fashion, cruising through to the knockout stage as they finished second in their group with 11 points courtesy of three victories and two draws, having only suffered a solitary defeat against Brazilian giants Flamengo.
They then met fellow Argentinian side Colon in the round of 16 and managed to go into the second leg on level terms as Alan Franco tied the home game at 1-1 in the dying embers after Ramon Abila had put their visitors ahead.
Federico Girotti gave Pedro Caixinha's side an aggregate lead soon after half time away from home, and Angelo Martino sealed their progression to the final eight with an injury-time goal.
In their trip to Velez Sarsfield for the first leg, La T went two goals behind but were able to draw level in the final 10 minutes through Michael Santos and Rodrigo Garro, only to concede again in injury time, leaving them with a deficit to overturn on Thursday.
Now on the back of a 2-0 league win over Argentinos Juniors, thanks to goals from Garro and Jose David Romero, to climb to 23rd spot in what has been a tough Argentine Primera Division campaign thus far, La T will be desperate to come from behind on home turf and book their place in the semi-finals of South America's premier competition.
Their visitors had a tougher start to life in this year's Copa Libertadores, sitting at the bottom of their group with just two games to go as they had just two points.
A 3-2 away victory over Nacional, thanks to Maximo Perrone's 94th-minute winner, saw them leapfrog their opponents and Bragantino, and El Fortin held on to second spot with a 4-0 thrashing of Estudiantes, booking a round-of-16 tie with Argentinian giants River Plate as a result.
Lucas Janson put Alexander Medina's side ahead in the 15th minute of the first leg, and they would go on to remain ahead by one goal over the next 165 minutes, eventually progressing to the quarter-finals with an impressive 1-0 aggregate triumph after two resolute displays.
Janson was again amongst the goals in their home leg against Talleres last week, putting them 2-0 ahead with a brace, and they have Julian Fernandez to thank for their lead coming into Thursday's trip as he restored the advantage with a goal in the dying embers.
Having seen their domestic struggles continue with a defeat to Union last time out, seeing them drop to 26th spot in the Argentinian top flight, El Fortin will be desperate to defend their lead on Thursday and advance to the final four.
Talleres Copa Libertadores form:
Talleres form (all competitions):
Velez Sarsfield Copa Libertadores form:
Velez Sarsfield form (all competitions):
Team News
Talleres may make several changes from the side that started the first leg last week, after Michael Santos and Rodrigo Garro both came off the bench to score in the final 10 minutes.
As a result, front man Federico Girotti could see his place at risk, having only found the net once in nine Copa Libertadores appearances this season.
Rodrigo Villagra has been a mainstay at the base of midfield, and he should again operate alongside Christian Oliva.
Winger Lucas Janson will continue to be a key man for Velez Sarsfield, having taken his tally to seven Copa Libertadores goals for the campaign with his brace in the first leg, with 15 to his name in 34 appearances across all competitions.
Julian Fernandez will be vying to start on the other flank, after the 18-year-old scored a late goal off the bench, while Lucas Pratto should again lead the line.
As they aim to defend their lead, Uruguayan veteran Diego Godin may also be called into the starting XI, with the former Atletico Madrid captain arriving from Brazilian champions Atletico Mineiro in June.
Talleres possible starting lineup:
Herrera; Benavidez, Catalan, Suarez, Diaz; Villagra, Oliva; Valoyes, Garro, Godoy; Santos
Velez Sarsfield possible starting lineup:
Hoyos; Jara, Godin, De Los Santos, Ortega; Perrone, Garayalde; Orellano, Bou, Janson; Pratto
We say: Talleres 1-1 Velez Sarsfield (Velez Sarsfield win 4-3 on aggregate)
If last week's first leg is anything to go by, Thursday's contest should be an exciting one, albeit with a different dynamic as Talleres look to come from behind while their visitors set out to hold their lead.