The Colombian’s effort early in the second half proved enough to earn the Seagulls a fully deserved win over the Champions, as Graham Potter’s side kept their fourth clean sheet in a row.
For Liverpool, though, they are now seven points behind Manchester City at the top of the table ahead of their trip to the Etihad Stadium this weekend after suffering back-to-back home defeats for the first time in seven years.
Brighton were dealt a double injury blow in the build up for kick off, with neither Alexis Mac Allister nor Joel Veltman fit enough to even make the bench. Alzate and Dan Burn came into the starting line up in their place.
Liverpool also had their own injury woes, with Allison unwell so there was a start for Caoimhin Kelleher in goal. In the second of two changes, Roberto Firmino was restored to the side at the expense of Divock Origi.
It was Jurgen Klopp’s side who created the first chance early on, with Jordan Henderson playing through Mo Salah. The Egyptian managed to find space between wing-back Burn and Adam Webster, but through on goal could only fire over the bar.
However, that turned out to be the only serious threat on Robert Sanchez’s goal in the first half. Brighton were disciplined in their shape and organisation when defending whilst also showing demonstrating attacking threat when going forwards.
24 minutes in Leandro Trossard and Solly March combined down the right to set up Neal Maupay, who could have taken the shot early but instead evaded a couple of challenges before his blocked effort dropped to Burn in space, but he side-footed over in front of an empty Kop from eight yards.
March then had a couple of efforts at Kelleher without troubling the Liverpool keeper, before Albion had a good chance to get the breakthrough in first half added time.
Maupay did well to rise above Henderson to meet Pascal Gross’ cross from the right hand side, but could only glance his header over the bar.
Klopp would have wanted a response from his side after a lacklustre first 45 minutes, and they sought after the opening goal straight after the break.
Xherdan Shaqiri’s dangerous ball through to Salah was intercepted by Lewis Dunk, and the Brighton skipper then did well to block Firmino’s goalbound effort. The Brazilian then had a low effort deflected wide of the post but it was Brighton who got the breakthrough after 56 minutes.
Gross was afforded room on the right to whip the ball in and he picked out Burn at the far post with a deep cross. The towering defender-come-wing back, who seemed to enjoy breaking forward, did well to head the ball across goal and Nat Phillips’ clearance ricocheted back off a combination of Alzate and Trossard and the Colombian appeared to get the final touch.
Back came Liverpool. Webster was alert and did well to clear the danger when Firmino looked to be in after James Milner dinked a free kick through, before Salah fired a first-time shot wide of the top corner after Trent Alexander-Arnold pulled the ball across to the Reds forward.
However, for all their defending Brighton continued to press forward when the opportunity came and were denied a second goal with 15 minutes to go. Dunk had a header from a corner blocked and the ball eventually dropped to Gross, who curled a low shot towards the bottom corner which Kelleher did well to push away.
In stoppage time, Liverpool had one last chance to get something from the game. In came Alexander-Arnold’s corner, but out came Sanchez to claim the ball and with it seal a great three points for the Seagulls.
It was far from a backs-to-the-wall performance by Brighton, and this victory – which lifted them above Newcastle and Burnley into 15th – will do wonders for confidence.