Quarter-final draw: Morton v Dundee Utd, Celtic v Alloa, Rangers v QoS, Aberdeen v St Johnstone
FT: Ayr United 1-2 Aberdeen, Celtic 5-0 Motherwell, St Johnstone 3-2 Hearts
St Johnstone v Hearts (19:45)
Robbie Muirhead comes into the Hearts starting line-up this evening. Alim Ozturk and Prince Buaben are also back, while Faycal Rherras has a minor injury, and Sam Nicholson and Tony Watt drop to the bench.
Chris Kane leads the Saints attack, with Steven MacLean among the subs, while Paul Paton and David Wotherspoon also come into the side.
Image source, SNSSt Johnstone v Hearts (19:45)
St Johnstone: Mannus, Scobbie, Alston, Anderson, Wotherspoon, Swanson, Shaughnessy, Paton, Easton, Kane, Craig. Subs: Clark, Millar, MacLean, McKay, Coulson, G. Hurst, Comrie.
Heart of Midlothian: Hamilton, Paterson, Ozturk, Souttar, Rossi, Djoum, Buaben, Cowie, Walker, Muirhead, Sammon. Subs: Noring, L.Smith, Oshaniwa, Nowak, Zanatta, Nicholson, Watt.
St Johnstone v Hearts (19:45)
The last time St Johnstone and Hearts met in the League Cup was in the 1998 semi-final.
Hearts were the Scottish Cup holders at the time, but were torn apart as Saints romped to a 3-0 win.
Image source, SNSAyr United v Aberdeen (19:45)
Niall McGinn and Adam Rooney return to Aberdeen's starting line-up after coming on as substitutes against St Johnstone on Sunday.
Paul Cairney, with plenty of top-flight experience, is one of Ayr's attacking threats.
Image source, SNSAyr United v Aberdeen (19:45)
Ayr United: Fleming, Devlin, Boyle, Murphy, Meggatt, Adams, Cairney, Crawford, Forrest, Thomas, McGuffie. Subs: Hart, Wardrope, Donald, O'Connell, Gilmour, Rose, A.Johnston.
Aberdeen: Lewis, Logan, Shinnie, Considine, Reynolds, McLean, Burns, Rooney, McGinn, O'Connor, Jack. Subs: Alexander, Stockley, Storey, McKenna, Storie, Wright, Nuttall.
Ayr United v Aberdeen (19:45)
Ayr United and Aberdeen do not meet too often and the last time the two went head-to-head was in the League Cup in 2008.
That day Chris Maguire fired the only goal of the game in the first half to secure the Dons' progression.
Andrew Considine is the only survivor of the Aberdeen team that night.
Image source, SNSCeltic v Motherwell (19:45)
Leigh Griffiths, Stefan Johansen and Efe Ambrose are unavailable for Celtic tonight due to suspension, while Kolo Toure is rested. Scott Sinclair makes his first Celtic start, while Saidy Janko, Emilio Izaguire and Tom Rogic also come in.
Captain Keith Lasley returns from a ban for Well, who include new signing and recent trialist Craig Clay in their starting line-up.
Image source, SNSCeltic v Motherwell (19:45)
Celtic: Gordon, Janko, Lustig, O'Connell, Izaguirre, McGregor, Brown, Forrest, Rogic, Sinclair, Dembele. Subs: Fasan, Ciftci, Armstrong, Christie, McCart, Henderson, Ralston.
Motherwell: Samson, Tait, Hammell, Heneghan, McManus, Cadden, Lasley, Chalmers, Clay, Johnson, McDonald. Subs: Brill, Laing, Ainsworth, Lucas, Thomas, Ferguson, Mackin.
Celtic v Motherwell (19:45)
In three out of the four matches between Celtic and Motherwell last season, Mark McGhee's men made life very difficult for the Glasgow side.
Image source, SNSLouis Moult (left) led the celebrations as Motherwell beat Celtic in December
Each side claimed a 2-1 away win and Celtic were 1-0 winners at Fir Park but Well were heavily beaten 7-0 at Celtic Park on the last day of the league season.
Scottish League Cup (19:45)
Unlike their respective opponents this evening, Ayr United, Motherwell and St Johnstone all featured in the newly-formatted first round of the Scottish League Cup.
At that group stage, matches drawn after regulation time went to penalties with the winner of the shoot-out taking two points and the loser getting one.
However, from this round onwards it's a straight knockout with extra-time and, if need be, penalties in the event of drawn matches.
All five of last night's ties were settled in 90 minutes so we could get the first extra-time of this season's competition tonight...
Good evening if you are just joining us and welcome to this evening's Scottish League Cup last-16 coverage.
The three remaining second-round ties take place this evening:
Ayr United v Aberdeen
Celtic v Motherwell
St Johnstone v Hearts
Motherwell have signed attacking midfielder Craig Clay on a two-year deal after he impressed on trial.
Image source, SNS#bbcsportscot
Ronnie Allan on Facebook: Unfortunately, looks like he is going west.
Dundee forward Greg Stewart has turned down the opportunity to join Birmingham City after a fee in the region of £500,000 plus add-ons was agreed.
Image source, SNSScotland winger James Forrest has signed a new deal to keep him at Celtic until 2019.
Image source, SNS#bbcsportscot
Jason Marr's first-half strike earned Alloa Athletic a place in the Scottish League Cup quarter-finals at the expense of Premiership opponents Inverness CT.
Jack Ross's side made it six wins out of six in all competitions and go into tonight's draw for the last eight.
Read Martin Dowden's match report here.
Image source, snsAlloa made it six wins from as many games this season