Ralph Hasenhuttl's effect on Southampton has been significant. He has introduced intensity and belief. Even a little bit of luck. But sometimes you just have to hold your hands up and say you were beaten by the better team.
The Austrian's side lost to a superior, more streetwise opponent, who won for just the second time at St Mary's.
It was an impressive victory from an injury-ravaged West Ham, and aside from the nous of Manuel Pellegrini, much of the credit must go to Lucasz Fabianski, Declan Rice and two-goal Felipe Anderson.
Anderson, West Ham's only outfield player to start every game, hit his seventh and eighth Premier League goals to steer West Ham to a come-from behind victory, their fifth in six matches.
But Pellegrini said his match-winner still has work to do following the victory which helped the Hammers to 15 points in December, the club's record Premier League points haul in the month.
'Of course he is a different player, a player that in every game makes important plays - he will continue improving.
'He still loses too many balls, maybe because he must understand the Premier League is difficult if you keep the ball in your feet.'
The visitors were also indebted to another summer buy, with the £8million they paid Swansea for Fabianski one of the smartest bits of business in recent history.
He hasn't missed a minute this season and the Pole was superb here, denying Southampton a certain opener twice before Nathan Redmond finally scored a contentious opener.
He is brave, positionally solid and makes some superb saves. He fully deserved the frequent chants of: 'Super, super Fab' from a boisterous away support.
It was a game of ebbs and flows. Southampton started like a train with Nathan Redmond and Danny Ings going close inside the first three minutes. Steadily, West Ham began to assert themselves.
They were big at the back and squeezed the hosts. Hasenhuttl likes to use his wing backs to launch attacks, but Jan Valery and Matt Targett were preoccupied with protecting their flanks rather than getting forward.
With mentor Mark Noble on the bench, Rice controlled midfield on the ground where he made his first Premier League start. 'Sign him up, sign him up, sign him up,' the West Ham fans sang of the 19-year-old, who has 18 months left on his current contract.
On this evidence, they should do just that. He is one of those players who appear to have all the time in the world on the ball, capable of spreading the ball wide and short.
He never puts a team-mate in danger, but when his side is up against it, he harries and chases.
Pellegrini gushed about the midfielder's attitude and ability, saying: 'Seeing Declan work every day it's difficult for me to be surprised with him. He always wants to learn more. The media start talking about his contract. Every day he is working hard. He is just focused on playing.'
Under Mark Hughes, Southampton struggled to find a suitable system. They struggled full stop, with Hughes winning thrice in his 22 games in charge. But under the pragmatic Hasenhuttl, for whom 4-2-2-2 is his favoured formation, Southampton have switched to a 3-4-3.
He was forced into a change with captain Pierre-Emile Hojbjerg suspended. Mario Lemina slotted in central midfield, but failed to assert himself on the game like the vocal Dane.
Three times in the first half Lemina fell asleep on the ball, and each could have cost him team. While West Ham just shaded it at the break, if you don't put away your chances, you run the risk of being beaten. Grady Diangana and Lucas Perez were guilty of squandering gilt-edged chances and Robert Snodgrass went close from distance before the break.
Southampton were by no means out of it. They have a resilience nowadays, and their heads don't drop. This was in evidence at the start of a breathless second-half. Lemina's cross from the right wreaked havoc.
The ball fell to Armstrong, with Romeu firing in the first shot. It fell to Redmond, who shot. Fabianski saved. Romeu shot again. Fabianski saved again. And then Redmond, who was being played onside by Diangana, was instrumental in bundling it home.
West Ham thought it was with a hand, but the goal stood. 168 seconds later they were level. Felipe Anderson struck a beauty from the edge of the area, controlling Lemina's clearing header and beating McCarthy. Armstrong tested Fabianski from distance, and then Anderson struck again.
On the break, former Saint Michail Antonio looked up and fired a crisp pass behind Southampton's defence, the Brazilian controlled the ball twice before beating McCarthy. 'Oh when the Saints go 2-1 down!' the away fans jeered.
Dressed in black, Hasenhuttl patrolled his technical area as his side pushed for an equaliser. They huffed and they puffed, but the house did not blow down. Targett's cross eluded substitute Shane Long, and Lemina was denied by Fabianski. After the game,
Hasenhuttl agreed that his side looked tired, after seeing Southampton throw away more points from a winning position.
'I tell my players that this is Premier League and if you make easy mistakes like the second goal you don't deserve to win. It was too easy how we gave our 1-0 lead away.'
Asked if the result was a fair one, he added: 'I don't know. It doesn't interest me really whether it's fair or not. I want to win if it's unfair. 'We gave it away too easy. That's what I say. We don't lose a game. Either we win or we learn. Today was a big learn,' he added.