Aston Villa's biggest improvement might be the players who aren't starting

One of the most encouraging aspects of Aston Villa's recent performances has been the quality of the players coming into the team and making an impact, because while we've had some outstanding starting elevens during Unai Emery's time at the football club, I'm not sure we've ever had quite the same level of competition throughout the squad as we do at the moment.

That's an interesting position to find ourselves in considering the number of established players Villa lost during the summer, because there were understandable concerns about how quickly the replacements would adapt and whether the overall quality of the squad would suffer. What we're seeing now suggests that the recruitment has not only replaced much of the talent that departed, but also created a situation where Emery has more genuine options available to him.

The victory over Manchester City was another excellent example, particularly when you consider the contribution of Ibrahim Mbaye, who came off the bench and immediately made an impact by providing the assist for Nicolas Jackson's second goal. It's one thing having talented players among the substitutes, but it's another entirely when those players are capable of entering a game against opposition of City's quality and making such an important contribution.

That ability to change games through substitutions is something Villa haven't always possessed to the same extent, and I think it's going to become increasingly important as the season progresses. The demands of competing in the Premier League and Champions League are enormous, and there will inevitably be occasions when players need resting, performances dip or Emery simply wants to approach an opponent differently.

What I find particularly interesting is that the manager appears completely comfortable leaving expensive or high-profile players out of the squad altogether when he believes other options are better suited to the job. Alejandro Garnacho and Taylor Harwood-Bellis weren't involved against Manchester City, despite arriving during the summer with significant expectations attached to them, but that doesn't necessarily tell us anything negative about their futures.

It tells us that Emery is selecting players based on what they're currently producing and what he believes the team requires, rather than allowing transfer fees or reputations to influence his decisions. Garnacho had an encouraging cameo in the previous game and may well find himself back in the side at some stage, but there's no reason for Emery to disrupt something that's working simply to accommodate a player who arrived with a bigger profile.

Alysson is probably the clearest example of that approach, because I don't think many supporters would have expected him to start three consecutive games at this stage of the season. There were questions about what he would offer Villa when he arrived from Brazil, but every challenge he's been presented with so far has been met with an encouraging response.

His understanding of Emery's methods, particularly without the ball, has impressed me enormously, and he's demonstrating that he can contribute to the team even when he isn't necessarily producing spectacular attacking moments. The work rate, positioning and willingness to carry out the tactical instructions are all there, and that's allowing him to establish himself in a side where competition for attacking positions is fierce.

There's also the trust Emery is showing in Brian Madjo, because bringing a 17-year-old into a game against Manchester City says an awful lot about the confidence the manager has in him. Jackson had spent the afternoon causing City's defenders enormous problems, and rather than simply introducing an experienced player to protect the result, Emery was prepared to give Madjo another opportunity to contribute at the highest level.

I think there's an important psychological element to that as well, because young players who are trusted in those situations inevitably begin to develop a greater belief in their own ability. Madjo has already started against Paris Saint-Germain in the UEFA Super Cup, and being introduced against Manchester City provides another experience that should help accelerate his development.

The same applies to Mbaye, who has gone from being a young player on the fringes at Paris Saint-Germain to somebody making a decisive contribution in one of Aston Villa's biggest Premier League matches of the season. Those experiences are invaluable, particularly when they're happening within a team that is winning games and playing with confidence.

There will be difficult decisions ahead for Emery, and some players will inevitably be disappointed when they're not selected, but that's the reality of having a strong squad. The important thing is that everybody understands the standards required and recognises that opportunities will come if they continue working and performing at the necessary level.

For me, that's one of the biggest differences between this Aston Villa squad and some of the previous groups we've seen under Emery. We know the starting eleven can compete with anybody on its day, but we're now seeing evidence that the players outside that eleven can make meaningful contributions as well.

If Villa are going to compete towards the top of the Premier League while managing another demanding European campaign, that depth could prove every bit as important as the quality of the players who start the biggest matches.