Cardiff City were knocked out of the FA Cup on Tuesday night as they lost on penalties against Championship rivals Reading.

The Bluebirds were 2-0 up just after half time but conceded twice late on as the Royals took the game into extra-time.

Neil Harris' side then scored to make it 3-2 just three minutes into extra-time but Reading snatched another late equaliser before winning the tie on penalties.

Here's THREE things we learned from Cardiff's cup defeat to Reading...

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Their defence remains shaky

The defence continues to look like it's going to leak goals. Compared to the defensive strength Cardiff showed when they were last in the Championship, this side are almost incomparable. They need to tighten up at the back and then focus on their firepower in the final third.

Aden Flint and Sol Bamba featured in the game last night and will both be disappointed in their performances. The Royals scored from three crosses, which is disappointing for the centre-backs and shows a real lack of organisation at the back.

Robert Glatzel can finish

Glatzel showed last night that when presented with an opportunity, he knows where the back of the net is. He needs more creativity from the Bluebirds midfielders and if he gets that, then he could well be a striker that can score regularly.

Glatzel has been poor throughout the campaign but hasn't had a huge amount of chances, despite leading the line for much of the season. On Tuesday night, he latched onto a great through ball before taking a few touches and finishing calmly past Sam Walker in the Reading goal.

He needs more opportunities to do that in the future.

Flint shouldn't be on penalties

It was a very strange decision from Harris to allow Flint to take the first penalty. The tall centre-back strode up and missed as his effort was saved by Walker.

It proved to be costly and set the tone for the shootout as Cardiff went onto lose 4-1 on penalties. It's decisions like this one, that at times can leave the supporters perplexed and wondering what the manager was thinking in that situation.