After suffering a heavy defeat at the hands of Manchester City on Wednesday, it was vitally important that West Ham bounced back on Saturday with a positive performance at the very least.
Hammers fans got that and more on their trip to Southampton where they saw their team pick up a massive 3-1 win over the Saints.
Goals from Andy Carroll, Pedro Obiang and Mark Noble gave the Irons victory with Southampton unable to deal with an accomplished team performance from Bilic's men.
It was a win that saw West Ham leapfrog Southampton in the table and move into the top half, having been a point behind Claude Puel's team heading into the fixture.
An exciting game from start to finish, there was plenty to take from the match.
Here are the FIVE lessons we learned from the encounter...
Andy Carroll is in peak form
With four goals in his last four games, it's clear Andy Carroll is currently performing at the peak of his powers. It's a massive positive for Bilic who had been missing an effective presence in the final third in the first half of the season.
If he can keep Carroll fit and healthy in the months to come then the Hammers should finish the season strongly and end up comfortably inside the top half of the table.
That'll certainly be the case if they can perform like they did at St. Mary's on a consistent basis.
Southampton's defensive crisis is real
With Virgil van Dijk out for two to three months and Jose Fonte having left for Saturday's opponents West Ham in the January transfer window, Claud Puel has a real defensive problem on his hands.
The hole left by both defenders is massive and we're not sure if the likes of Jack Stephens can step up into their place.
Unless Puel can find the right defensive blend then they're not going to have a consistent series of results and could find themselves adrift of the top half of the table and have no chance of reaching European positions.
The League Cup Final must be a real concern for Saints fans too with a big improvement needed at Wembley if they're to secure silverware against Manchester United.
West Ham aren't as bad as some results suggest
Bilic has had to answer serious questions in recent weeks after some heavy defeats but Saturday's result at St. Mary's proves that rumours of their demise have been slightly exaggerated.
The Irons are a very effective unit on their day and Bilic has them organised into a system that works for them against most teams outside of the top 6.
They need fresh personnel to take them to the next level but with the players available to him, Bilic is doing a fine job in his guidance of the Hammers.
Now they're in ninth, their next targeting will be overtaking West Brom in 8th, who sit five points ahead of them in the table. They have a perfect opportunity to haul in some of that lead next week when they host Tony Pulis' side at the London Stadium.
Gabbiadini is a quality acquisition
Manolo Gabbiadini just needed one chance to announce his arrival on the Premier League scene from Serie A. He took his goal expertly early in the first half, making the perfect impression on his new home supporters.
He could prove to be a very fine acquisition indeed and fans will be hoping he can show more of that goal threat in the weeks and months to come.
He had another chance in the second half to take Southampton back to 3-2 but his curling shot went just wide and high of Randolph's goal. He may not have taken that one but he showed enough to think that he'll be a success in the Premier League.
Obiang is an underrated Irons player
While the likes of Andy Carroll and Michail Antonio may have been stealing the headlines in recent weeks, Pedro Obiang has been an underrated component of West Ham's resurgence.
He scored his first ever goal for the club on Saturday, giving them the vital 2-1 lead they needed to go on and win the match.
He was a key presence in the heart of the Hammers midfield with his tackling and energetic style giving Bilic's boys the platform needed to build into the final third.