DAVE Artell admitted Crewe's heavy defeat at Fratton Park this afternoon was largely "self inflicted" as uncharacteristic defensive errors proved costly.

His side travelled south with one of the best rearguard records in League One, having conceded only nine in their previous 12 games, but were undone by some poor individual mistakes.

Republic of Ireland attacker Ronan Curtis feasted on them to grab a first-half double and then second-half strikes from Pompey captain Tom Naylor and top scorer John Marquis added to the misery before Oli Finney converted a stoppage-time penalty.

"If you give any team a two-goal start, as we did, then it's going to be a tough afternoon," admitted the Crewe boss.

"I thought there wasn't anything in the game in the first half, apart from us gifting them two goals. If anybody looked promising it was us - but goals change games.

"It became a long afternoon and it was mostly self-inflicted. I'd rather concede goals by trying to play football, but there is a limit to that. And rolling the ball to the opposition twice is beyond that limit."

The irony is the scoreline bares little relation to the possession stats, which showed Crewe had more than twice as much as Pompey.

Crewe were missing the injury Mikael Mandron and Offrande Zanzala made his first start in the league up top. But they still posed a first-half threat and Craig MacGillivray needed to push over Finney's blast.

But some poor passing at a free kick in the visiting half allowed Ellis Harrison to steal possession and Curtis was set up to scuff a finish past Will Jaaskelainen for the opener (15).

Omar Beckles was then caught in possession and Curtis forced home his second (40).

Two goals in the first 11 minutes of the second half killed the game off. Naylor drove in from 20 yards (50) and after Pompey were wrongly awarded a throw-in, a quick delivery ended with Marquis the quickest to react after he drove against the bar, with the frontman heading home the rebound for the fourth (56)

Artell made use of the substitution rule changes voted in this week, bringing on all his permitted five, which included replacing Beckles with Olly Lancashire at the break.

And one of the replacements, Callum Ainley, struck the post late on before Crewe finally did get at least some consolation for their efforts when Finney fired home the penalty awarded for a handling offence (90+4).

Pompey boss Kenny Jackett revealed: "We did think if we won the ball back in the right areas there was space to exploit. Ultimately, that was the thing that got us the three points."