Neath may have had home advantage but Aberavon's recent cup win over Swansea showed their ability to perform when it really matters.
And they did it again on Easter Sunday to give them a confidence boost ahead of their SWALEC Cup semi-final against the same opposition on Saturday week.
The visitors were in control of the game from the moment Andrews scored a breakaway try in the first half.
And although Neath came back into the contest, it was the visitors who took the points, despite twice being reduced to 14 men.
Dai Langdon and Jamie Davies, who was on as a blood replacement for Craig Evans, had exchanged early penalties before Andrews put Aberavon 8-3 up with his side's first try.
Centre Jenkins then scored to extend the lead to 10 points before visiting prop Rowan Jenkins was sent to the sin bin.
After the break, Anthony Edwards became the second Aberavon prop to be carded by referee Tim Hayes.
Langdon's boot kept Neath in the game but they failed to make the most of their numerical advantage as the visitors held on.
At St Helen's, Wales U20 flanker Daniel Thomas scored a hat-trick in a pulsating Llanelli win over Swansea.
Both sides seemed to eschew defence in favour of attack but it was Llanelli who came out on top 35-38. Richard Williams and Thomas had exchanged early tries before Llanelli pulled further clear with a score from wing Kyle Evans.
It was all action and the home side soon hit back, No. 8 Dan Baker going over following a quick tap penalty from scrum half Jake Cole. But Thomas' second score saw his side lead 19-12 at the break.
A quiet opening to the second half belied what was to come as the tries continued to come. Baker used his pace and power to add his second before Thomas completed his hat-trick and Evans added his second.
The boot of Nicky Thomas kept the home side in contention and Jamie Thomas' converted try gave Swansea a shock lead.
But Justin James' match winning try maintained Llanelli's play-off push.
Their win aside, it was a good day for Llanelli elsewhere as Bridgend shocked Bedwas at the Brewery Field. The defeat means Bedwas stay in second place but are now only two points clear of Llanelli in third.
The Gwent side didn't look like losing when they were 23-10 up at half time, Stuart Thomas and Josh Davies crossing in the first half.
But two tries from Ashley Evans, added to Jamie Murphy's first half score saw the Ravens come roaring back and leave Bedwas looking over their shoulder.
In another local derby, Carmarthen Quins got the better of rivals Llandovery and leapfrogged them into fifth place as a result.
Head coach Steve Williams saw Rob Evans and Alex Pickersgill cross for his Carmarthen side in the 17-12 win.
"We were up against it at times but everyone put their shoulders to the wheel and it is a great feeling to do the double over the Drovers," he said.
"We have trailed them all season but we have been improving steadily despite limited time and opportunity to train in the bad weather.
"We were also disrupted by some late withdrawals but the character and commitment of the whole side shone through."