I don't know if Markovic has impressed enough in training to book a place in the matchday squad, but on current form, Ibe probably has to look nervously over his shoulder to see if someone's coming in to take his place soon for a while. It doesn't mean he's shit, and it shouldn't be a shame though. As some have mentioned in the post-match analysis, Sterling dropped back to the U21 level for a little bit in the second half of his first full season, and then sat out a few months to start the second season before being recalled in November and then hitting form and going on a tear the following month. There's no guarantee that the same trajectory will apply to Ibe, but I trust the management in being able to help him fulfil his promise given the experience they have in working with young players.
Back to Markovic - I don't think he should be a shoo-in even if Ibe gets dropped. Teixeira has done impressively in pre-season and in the U21 game last week, so I'd say he should get as good a look as Markovic if Ibe's position does get threatened. The price we paid for Markovic was a mistake, but what's done is done and we should just pick and play the best available player - if Teixeira's performance and attitude is better, then he should be ahead in the pecking order. Kent would probably be a good shout too to get a promotion, and is more of a like-for-like replacement. He's probably headed out on loan though. Bottomline is, there's a chance now for Markovic to get a recall, and he needs to do enough now in training to press his case.