Millwall beat Stevenage 2-0 to progress to the second-round of the Carabao Cup.

Tom Elliott’s first goals for the club made it a comfortable evening for the Lions.

Here are five things we learned…

Elliott means business

Lee Gregory and Steve Morison have enjoyed two successive prolific seasons for Millwall, without any real competition for places. Neil Harris addressed that earlier this summer by bringing in Elliott.

In his first start for the club, the big striker capped off a dominating display with a brace. He was in the right place at the right time to head in his second-half goals.

With Gregory an injury doubt for the Bolton clash, Elliott could have another chance to impress. He has certainly given Harris something to think about for Saturday.

Fred Onyedinma shines

He started up front with Elliott, but moved into a more natural right wing position when Jake Cooper was subbed off – and looked more comfortable out wide.

His pace and power was too much for ex-Millwall left-back Joe Martin to handle. Onyedinma put Elliott’s opening goal on a plate with a lovely dinked cross. He’s not a regular starter in Harris’ side, but he proved his worth and exciting potential with a fine performance.

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Fred Onyedinma | Picture: Benjamin Peters Photography

He has the ability to play as a number 10, striker or winger and that will make him an asset to the Lions in a gruelling Championship season.

Ben Thompson confidence worry

He is Millwall through and through and will always be a fans’ favourite. But it didn’t stop home fans groaning after the midfielder lost the ball too many times.

Thompson lost his place in the starting eleven towards the end of last term, and was an unused sub in Millwall’s season opener with Nottingham Forest last Friday.

MORE: Player ratings from Millwall’s Carabao Cup first-round win over Stevenage

He is currently behind George Saville and Shaun Williams in the pecking order at the Den. His performance against Stevenage showed signs of a player struggling for confidence.

He needs to perform well in future Carabao Cup games to force his way back into Harris’ first-team plans.

Injury concerns for Millwall

One negative on the night for the Lions was losing key duo Cooper and Gregory to injury. Cooper was forced off with an ankle problem, while his replacement, Gregory, could not continue in the second-half after feeling his hamstring tighten up.

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Lee Gregory in action against Stevenage | Picture: Benjamin Peters Photography

Harris conceded that the pair are early doubts for Saturday’s home game against Bolton. And if they don’t make it back in time, it will be a massive blow. Despite his open-goal miss, Gregory caused Forest’s back-line all kinds of problems at the City Ground – and Cooper was a steady presence at the back.

Squad depth is strong

With Cooper and Gregory likely to miss the Bolton game, Byron Webster and Elliott will be capable replacements. Webster has bags of Championship experience, while Elliott showed his class in the Carabao Cup.

It highlights the strength in depth that Millwall have, and it’s something that will be so important in a gruelling Championship campaign.

If James Meredith has a bad game, then Tony Craig will be ready to take his place, and if Aiden O’Brien is struggling for form, then David Worrall and Onyedinma will be breathing down his neck.

There is healthy competition in the squad, which will only improve the players.