Pontypridd start as favourites to retain their Swalec Cup crown but Aberavon will no doubt be keen to prove the bookies wrong when they take on the Principality Premiership leaders at Bridgend's Brewery Field.
Ponty were comfortable 33-10 victors when the two teams met at this stage of the competition last season and they are currently nine places and 42 points better off than the Wizards in the league, having won 15 and drawn one of their 18 Premiership fixtures to date.
The reigning Swalec Cup Champions thumped Aberavon 42-10 at Sardis Road just 10 days ago but there is little danger of Ponty being complacent given that Aberavon triumphed 29-27 at Talbot Athletic Ground three days earlier. A last-gasp drop goal from full back Richard Carter saw the underdogs overturn a 21-point deficit on March 29 but a repeat on neutral ground would be an even bigger upset seeing as Pontypridd haven't failed to reach the final since they were beaten by Carmarthen Quins at this stage of the competition in 2010.
Aberavon will have revenge at the back of their minds as last year's semi-final defeat was preceded by heartbreak against the same opposition in a thrilling final 23 months earlier. Ponty were 35-24 winners in 2011 as they claimed their first Swalec Cup crown for five years.
The favourites head into the semi-final on a high having beaten RFU Championship outfit Cornish Pirates 16-14 in Penzance at the weekend to book their place in the last four of the British & Irish Cup but Aberavon have been in good form themselves of late. Jason Hyatt's men took a share of the spoils at high-flying Llandovery on Saturday and have won nine and drawn one of their 13 matches since the turn of the year.
The other Swalec Cup semi-final sees Cross Keys take on Llandovery at the Knoll with just one place and three points between them in the league standings.
The honours have been split in their two Premiership meetings this term, with Cross Keys winning 29-13 at Pandy Park at the end of September and Llandovery coming out on top 23-16 at Church Bank in late February. Their recent form is also pretty similar, with Cross Keys having won four games on the bounce prior to a surprise home defeat to Carmarthen Quins last week, while Llandovery's draw with Aberavon had been preceded by three league wins in four.
Both sides have tasted recent success in the Swalec Cup, with Cross Keys stunning Ponty to claim a first-ever title two years ago, five seasons after Llandovery earned their maiden Swalec Cup crown with a narrow win over Cardiff.
Llandovery edged past Swalec Championship winners Ebbw Vale in the quarter-finals three weeks ago, while Cross Keys were 25-10 winners over Cardiff at the Arms Park.
Check out the WRU website tomorrow for our previews to the Swalec Plate semi-finals between Glynneath and Merthyr and Llantwit Fardre and Rhiwbina and the Swalec Bowl ties featuring Llandudno and Clwb Rygbi Cymry Caerdydd and Llantwit Major and Old Illtydians.