Vincent Tan flew in on a big day of fun, fighting and focus in Cardiff.

Funny men Micky Flanagan and Jimmy Carr provided the jokes in shows at the Motorpoint Arena and St David’s Hall in the Welsh capital respectively.

Violence came in the boxing ring with Anthony Joshua and Carlos Takam going toe-to-toe at the Principality Stadium, while there was also a heavyweight clash on ice in Cardiff Bay where hard-hitting Cardiff Devils faced Coventry Blaze in a crunch cup clash.

Neil Warnock’s Bluebirds, though, stayed focused on their task of maintaining momentum in their promotion challenge. They  couldn’t win against a Millwall team who increasingly looked to hang on, but they fought every step of the way in a goalless draw.

It was a frustrating match for City and Warnock looked mystified by some of the refereeing decisions. Steve Martin was the official and he made a whole series of strange calls which upset the home team.

Bluebirds owner Tan was at Cardiff City Stadium for the second time in 10 weeks and he witnessed a fiercely contested match.

The player who impressed most was Callum Paterson, making his home debut when he replaced injured Joe Bennett at wing-back after 37 minutes.

Lee Peltier switched left, while Paterson slotted in on the right and gave Millwall major defensive problems.

Scottish international Paterson added attacking zip and energy down his side, linking beautifully with Nathaniel Mendez-Laing just after going on.

He sped away on a counter-attack and picked out Junior Hoilett at he far with a magnificent cross. The Canadian international chested down and went for goal with Millwall ‘keeper Jordan Archer making an outstanding save low down.

Soon after half-time Paterson was on the charge again when he surged into the middle and met a Peltier cross, outjumping Archer and heading towards goal. It looked a certain goal, but Paterson’s effort flew just wide.

Warnock set up his team with a three-man central defence involving captain Sean Morrison, Sol Bamba and Bruno Manga.

Millwall manager Neil Harris, a former Cardiff player, ensured his team stayed solid with two banks of four players in midfield and defence.

That left City outnumbered through the centre of midfield, where Joe Ralls and Craig Bryson found it hard to fill the gaps. A week earlier, during the win at Middlesbrough, both wing-backs had tucked in to help out, but Millwall were able to gain superiority far too often through the middle.

Bamba had a moment of real quality when he won a big challenge near halfway and slid a delightful low pass through the heart of Millwall’s defence for Danny Ward, whose shot was saved at full strength.

Then Bamba almost cost his team a goal when his back pass and former Wales international Steve Morison raced in on goal. Only a last ditch save by Neil Etheridge, blocking Morison’s effort, saved the day for Cardiff.

There were too many sloppy moments from a disjointed Cardiff team over the 90 minutes, but they stayed committed to the cause in a physical match.

Omar Bogle took over from lone striker Ward, who had worked bravely against two big central defenders, with just over 25 minutes left, while Lee Tomlin replaced Bryson after 74 minutes.

That was a bold, positive move by Warnock as he looked to find the fluency to open up Millwall. City switched to a back four with Bamba moving forward to take up a defensive midfield role.

Tomlin slotted into the number 10 role behind Bogle in a 4-2-3-1 system.

City weren’t able to find the goal they badly needed and now turn to next Tuesday’s home fixture against Ipswich Town.

Millwall were clearly delighted with their point, while Cardiff were left pondering what might have been with Wolves, just above them in the table, losing 2-1 against Queens Park Rangers.

There was a moment of late drama when Millwall’s Archer prepared to kick upfield and as he tossed the ball out of his hands to clear Tomlin flicked it away from him. There was no contact between the players, but referee Martin gave a free-kick to the visitors and booked the Cardiff man.

Cardiff City: Etheridge, Peltier, Morrison, Manga, Bennett (Paterson 37), Bamba, Mendez-Laing, Bryson (Tomlin 74), Ralls, Hoilett, Ward (Bogle 64). Subs not used: Tomlin, Feeney, Halford, Damour, Murphy.

Millwall: Archer, McLaughlin, Hutchinson, Cooper, Meredith, Wallace (Onyedinma 90), Tunnicliffe, Saville, O’Brien (Ferguson 78), Gregory (Elliott 78), Morison. Subs not used: Craig, Thompson, Romeo, Martin.

Referee: Steve Martin.

Attendance: 18,496.