Inter Milan s Italian head coach Simone Inzaghi reacts during the Italian Serie A football match between Inter and Lecce on March 5, 2023 at the San Siro (Giuseppe-Meazza) stadium in Milan. AFP
Friday's 2-1 defeat at relegation-threatened Spezia was the latest poor effort away from the San Siro and left Inter once again 18 points behind champions-elect Napoli.
Inzaghi and his team were booed and insulted by the Inter fans present at the Stadio Picco, who had to watch the son of AC Milan icon Paolo Maldini slot home the opening goal.
Inter have only held on to second place in Italy's top flight thanks to Lazio failing to win at Bologna on Saturday, but their bid to qualify for next season's Champions League is being damaged by their dreadful away form.
Inzaghi said "we won't be able to sleep" after Friday's hugely disappointing eighth loss of the Serie A season, which took their tally of goals conceded to 24 in 13 league away matches.
"We're not happy about our results away from the San Siro. Last year it was a different story," said Inzaghi.
"We have had some great results away, like at Barcelona (a 3-3 draw), and we know that we need to put in a great performance if we're going to reach the quarter-finals."
Inter's defensive wobbles were also present in their group stage campaign, with five goals conceded in matches at Barcelona and Bayern Munich.
And elimination on Tuesday would not only mean missing out on a first last-eight tie since 2011, it would also heap more pressure on Inzaghi with fierce rivals Juventus visiting the San Siro on Sunday.
One piece of good news is that Milan Skriniar might be ready to return from a spell on the sidelines with lower back pain.
Porto, gunning for a third quarter-final in five seasons, have been a bogey side to Italian teams in recent years and are aiming to add to the series of Serie A scalps which include Juventus and Roma.
The Portuguese champions had to come from behind when they knocked out Roma four seasons ago and have cause for optimism given how they performed in Milan last month.
Marko Grujic, Mehdi Taremi and Zaidu Sanusi all had great opportunities to score before Romelu Lukaku netted the only goal of the game shortly before the end.
However Sergio Conceicao again has to deal with important absences.
Gabriel Veron is out with an ankle injury and Evanilson and Galeno are both suffering from muscle problems. In addition, Otavio will be suspended and unable to play in the game.
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