Caretaker boss Wesley Carvalho is winless in their last two league games, while the away side seeks their first victory in four games.
Match preview
Despite Athletico's failure to win back-to-back games, they remain four points away from a Copa Libertadores spot, suggesting 11th place is not as awful as a cursory look suggests.
A broader examination of Carvalho's team shows one victory in their last five league matches, causing their slide in the standings in recent gameweeks.
They are guaranteed to remain in the Copa Sudamericana places regardless of this weekend's result, with 13th-placed Santos four points adrift of Athletico.
A return to winning ways is likely due to the strength of Carvalho's troops at Arena da Baixada, where they have won five in seven this season, suffering one loss.
With seven points secured from an available nine on their turf, victory on Sunday would be what the doctor ordered for Athletico.
As for Bahia, the relegation-threatened side could slide into the bottom four this weekend or open a gap on the sides doomed to lose their top-flight status.
Two points separate the 16th-placed team from Goias, who occupies 17th place but are on a three-game losing run.
A defeat for Tricolor and victory for Goias would see the former drop into the danger zone, an eventuality that adds pressure to Renato Paiva's team.
The away side have been wretched on their travels all season, picking up a sole victory — a 1-0 triumph over Vasco da Gama at the start of May — before falling to three defeats in the subsequent five.
They have failed to score in three of their recent road matches, adding to the feeling that a fifth loss on their travels could be in the offing at Athletico on Sunday.
Athletico Paranaense Brasileiro form:
W
D
L
W
D
L
Athletico Paranaense form (all competitions):
W
W
D
L
L
L
Bahia Brasileiro form:
D
D
W
L
L
D
Bahia form (all competitions):
W
L
L
D
D
L
Team News
Carvalho is not expected to alter Athletico's shape from the 3-4-3 utilised when they host Bahia on Sunday.
Thiago Heleno should retain his spot at the heart of the home side's defence despite a late sending-off in the Copa do Brasil on Thursday.
Vitor Roque has netted a goal each in his last four league outings, and the Barcelona-bound striker is the home side's most-reliable match-winner.
Raul Gustavo and Marcos Victor could make the Bahia bench after recovering from knee issues, but Matheus Bahia and Yago Felipe are absent through injuries.
Marcos Felipe made 10 saves in the cup defeat by Gremio in mid-week, including three from 12 yards, and the goalkeeper should play a pivotal part in Sunday's outcome.
The away side are expected to utilise either a 4-2-3-1 or 4-4-2.
Athletico Paranaense possible starting lineup:
Bento; Henrique, Heleno, Ze Ivaldo; Khellven, Erick, Moura, Christian; Bueno, Roque, Canobbio
Bahia possible starting lineup:
Felipe; Cicinho, Xavier, Kanu, Ryan; Acevedo, Rezende; Kayky, Cauly, Ademir; Everaldo