Ninety minutes is all that separates 10 teams from the Champions League group stages and the millions in TV revenue and prize money it brings. BT Sport's James Horncastle looks at the storylines...
"Kelechi Iheanacho is due a chance from the start. He signed a new long-term deal last week and has impressed on each of his cameo appearances this season, forcing the error for Paddy McNair's own-goal against Sunderland, setting up Nolito against Stoke and playing a magnificent dummy for another goal away at the Britannia."
Iheanacho to get his chance against Steaua
By anyone else's standards, the six goals Sergio Agüero has scored in his opening three games of the season for Manchester City would be all a manager could ask for and more. But Pep Guardiola is not any other manager. Indeed, it was mildly amusing to hear him warn Agüero not to get complacent after Saturday's win against Stoke.
"It is not enough to receive the ball from his teammates," Pep said. "He has to help us in the first pressure and run a lot and help us a lot with movement. Until now he's doing it and when that happens you are involved in defensive tasks and the offensive. You cannot be brilliant when you disappear when you [don't] have the ball. It's impossible."
Make no mistake, Pep is a hard man to please. But his insistence that City attack as a team and defend as a team shouldn't come as a surprise. When you appoint Pep, this is the minimum players can expect. "To create something, we need time," he admitted on the eve of the season. "But to play with soul, with something inside, we don't need time. We are not going to accept playing with soul. That is what I want from my players." And Agüero is no exception.
Pep claims City will make a few changes for Steaua's visit to the Etihad on Wednesday night. He can afford to experiment after last week's 5-0 win in Bucharest. Agüero deserves a rest. At the very least it would not only keep him fresh to score, but also to carry on his work off-the-ball with the same intensity Guardiola demands.
Kelechi Iheanacho is due a chance from the start. He signed a new long-term deal last week and has impressed on each of his cameo appearances this season, forcing the error for Paddy McNair's own-goal against Sunderland, setting up Nolito against Stoke and playing a magnificent dummy for another goal away at the Britannia. Back him to score on the Sportsbook at 8/11.
Rodgers' man-management reaping immediate rewards
Elsewhere in the play-offs, Celtic must be confident of returning to the group stages for the first time since 2013 after establishing a three-goal cushion in the first leg of their tie with Hapoel Be'er Sheva. It's only August but already Brendan Rodgers has made a noticeable impact in Glasgow. There has been praise in particular for his man-management.
For instance, Rodgers tactfully invited Scott Brown to his house for talks soon after taking the job and reassured the Celtic captain that he is still very much in his plans. Much has also been made of Rodgers changing the time of a training session to allow those Celtic players with families to spend more time with their kids on the morning they were due back at school.
Spirits are high in the camp and a positive approach on the pitch has gone a long way to reinforcing it. This, in addition to improved fitness levels, is the most noticeable difference with Rodgers' predecessor Ronny Deila. Leigh Griffiths has admitted Celtic would probably have crumbled last season when Be'er Sheva came back from 3-0 down to within a goal of an equaliser in the first leg. Instead, they were unfazed and pushed on, encouraged by Rodgers' bold substitutions and won 5-2.
While Rodgers' decisions had a clear logic to them - Be'er Sheva would leave space in behind as they piled forward to draw level - it was also maybe an admission that he couldn't trust his backline to defend the lead. Celtic were 3-0 up again at the weekend only for St Johnstone to bring it back to 3-2. However, another Rodgers attacking substitution, the introduction of Ryan Christie put the game beyond all doubt in stoppage time.
Celtic have got to get better at managing games. They'll give Be'er Sheva chances on Tuesday but Rodgers' has at least instilled Celtic with greater mental fortitude and the belief that they will always score at least one more than this calibre of opponent.
Roma to join Juventus and Napoli in Group Stage
Meanwhile, in Italy, Roma welcome Porto to the Olimpico with the regret that this tie hasn't already been put to bed. Totally in control for the first half hour at the Dragão, they deserved to be more than a goal in front. Thomas Vermaelen then single-handedly helped Porto back into the game with a red card on his debut.
Roma were down to 10 men for close to an hour and limited the damage to a 1-1 draw. Still, this team should be okay as long as Kostas Manolas recovers from a thigh injury in time and they keep all 11 players on the pitch. Porto are not the force they were in the past. Their most dangerous attacking players Vincent Aboubakar and Yacine Brahimi are for sale and yet to feature this season.
While Andre Silva looks like the striker Portuguese football has long been waiting for, scoring in every game he has played this season, it's unlikely he can turn this tie on his own. If Roma replicate the second half performance they put in against Udinese on Saturday, blowing them away 4-0, expect them to join Juventus and Napoli in the Champions League proper.