“It felt like there were lots of positives from today, our set-pieces were good but we will need to impress on the team the need to focus on the penalty concession. If we can halve that it will make a big difference,” he said.

“We need to stop the offload game - we know how dangerous that can be. That try on half-time was pretty unlucky. I think if we tighten up in a couple of areas to maintain that pressure we can get that momentum back.

“We have improved from the opening game with the time we have spent together and we will improve again before Saturday.”

Gatland’s forwards were dominant but the Lions backs were outplayed by the Blues, the worst performing of New Zealand’s five Super Rugby teams this season.

The Blues scored three tries to one with full-back Leigh Halfpenny’s boot keeping the Lions in the match with three penalties and a conversion.

The tour will only get more difficult for Gatland’s men, who face the table-topping, undefeated Canterbury Crusaders in Christchurch on Saturday.

New Zealand national coach Steve Hansen was watching from the stands and saw two-time World Cup winner Williams score a try and emphatically lay claim for a return to the All Blacks squad.

Blues winger Rieko Ioane also continued to press his case for selection for the three-test series against the Lions with his seventh try in six matches.

Prior to kick-off, there was a minute’s silence to honour victims of the London terror attacks, then the Blues performed a haka specially commissioned for the occasion.

The Lions came out of the blocks hard, claiming 73 per cent of territory and 63 per cent of possession in the opening 20 minutes.

They created early chances, with Jared Payne pouncing on a loose ball but putting too much power on his kick and failing to catch it in the in-goal area.

Blues fly half Stephen Perofeta then set up the opening try of the match, first turning the Lions defence with a cross-field kick then sending a long-range pass to put Ioane through on the wing.

Perofeta followed up moments later with a try-saving tackle on Payne at the other end of the field, forcing him into touch before he could ground in the corner.

The tourists continued to attack and were rewarded when Munster’s CJ Stander powered his way over from a line-ut drive after some dominant play from the Lions forwards.

Halfpenny added a conversion and a penalty to put the Lions ahead 10-5 before Williams sensationally stole the lead back right on half-time.

Perofeta’s penalty goal attempt struck the post and Williams was quickest to react as Lions winger Jack Nowell knocked the ball behind the try-line under pressure.

Williams sped between two defenders to get a hand on the ball and sneak the try under the posts, converted by Perofeta, that sent the Blues into the break 12-10 ahead.

Nowell made amends shortly after the restart when he launched a desperate tackle that denied Ioane a second try in the corner. 1

The Blues began to gain momentum and stretch the Lions’ defence, with the tourists’ task made more difficult when replacement centre Liam Williams was sin-binned for dangerous play.

But the Lions rallied and patiently worked the ball through the centre of the park, drawing two penalties to edge back into the lead at 16-15.

But Williams produced another magic moment to seize it back with six minutes remaining, breaking the line and offloading to West, whose lightning pace took him past four defenders and under the posts.

West kicked the conversion himself to make it 22-16 and despite the Lions throwing everything into attack during the final minutes they could not find a breakthrough.