Jack Harrison’s late equaliser for Leeds United prevented Millwall from ending the Championship leaders’ unbeaten run in a dramatic clash at the Den.

Jed Wallace opened the scoring when he raced onto a Jake Cooper flick-on at the back post, but the visitors responded minutes before injury time.

There were further tense moments between the two dugouts in a heated rivalry between the two clubs but in the end the points were shared.

Here are five things we learned…

A case of déjà vu for Millwall

In a game where the hosts played reasonably well to believe they deserved all three points, it came down to a late goal that whisked away hopes of a win.

This isn’t the first time Millwall have conceded late when leading this season – Swansea City and Middlesbrough have staged comebacks when they looked down and out.

A frustrating afternoon all-round.

Ryan Leonard impressed for his new club

Considering the limited amount of action he has had this season, the midfielder’s debut gave reasons to be hopeful.

The departure of George Saville to Middlesbrough left the Lions in need of a convincing first-team replacement and this cameo showed promise.

Let’s see what he will bring when he’s fully integrated into the starting 11 and fully fit.

An alternative weapon for Harris?

Following on from Leonard’s first outing, his long throw which led to Wallace’s opener was an interesting tactic which paid dividends.

Cooper nodded the ball to the back post and left the defenders unable to recover in time as the winger hit the ball off the post and in.

It’s just another tactic available at Harris’ disposal.

Ben Amos was superb

The on-loan goalkeeper, who joined the club following a spell with Charlton Athletic, made several great stops which prevented Leeds from equalising – and taking the lead.

He thwarted Tyler Roberts when the striker broke free in a near one-on-one before Luke Ayling was denied at his near post with a strong hand.

It took a long-range effort which parted through a sea of navy blue shirts to get the equaliser, which says something at least.

Despite refereeing controversy, Leeds were worth a point

Chris Kavanagh’s decisions were bizarre at times. Giving free-kicks which looked dubious while some corners and throw-ins looked to go to the wrong team.

But overall, Leeds heaped pressure on Millwall and forced the hosts to defend for their lives.

Roberts asked questions of Cooper and Murray Wallace, while Ayling’s marauding runs down the Lions’ left side proved hard to deal with.