Old cup adversaries Chelsea and Middlesbrough meet for the first time in 26 years in the Carabao Cup at the Riverside Stadium this evening.

This is the Blues’ 16th Carabao Cup semi-final. The last one that involved an opponent from the Football League was in January 2007. It ended in a 5-1 aggregate victory for Chelsea over Wycombe Wanderers.

Middlesbrough are entertaining their second Premier League visitors in four days. They lost 1-0 to Aston Villa on Saturday evening in the FA Cup third round.

However, the last time the Teessiders reached the last four of this competition, back in 2004, they went on to lift the trophy. They currently sit 12th in the Championship – four points off a play-off place – but have lost four of their last five home matches on all fronts.

Mauricio Pochettino’s men prepared for tonight's game by seeing off Championship opposition in the form of Preston North End in the FA Cup on Saturday. The Londoners are now unbeaten in 28 matches against lower-league opponents in domestic cups.

No matter what happens, this tie will make history as this season's semi-finals will be the last played over home and away legs following an EFL rule change. And as the Riverside is not suitably equipped, it has been decided neither semi-final tie will use VAR technology.

Route to the semi-finals

Chelsea team news

Pochettino has stated the same players that were available against Preston on Saturday will be available against Middlesbrough. That makes it unlikely Benoit Badiashile, Ben Chilwell or Carney Chukwuemeka will return from injury while Christopher Nkunku is ruled out.

However, Saturday’s rested regulars, including Conor Gallagher, Noni Madueke and Thiago Silva, could return to the starting XI at the Riverside.

As Pochettino has highlighted, the key to defeating Championship opponents is to match their effort and to set the tempo of the contest. The Argentine wants an improvement in mental and physical intensity following a tardy first half against Preston on Saturday.

The Blues eventually found a way through Preston's low block via an expert cross, the perfect ammunition for Armando Broja, who could again lead the line with Nicolas Jackson away on international duty at the Africa Cup of Nations.

The 22-year-old’s towering header, Alfie Gilchrist's first start, a proud Levi Colwill wearing the armband and a debut for Michael Golding made it a great day for Cobham at Stamford Bridge.

Along with potent delivery into the box, the Blues have added direct free-kick goals to our attacking repertoire. Raheem Sterling replicated the excellent technique used against Newcastle, but before those two just one of his 168 goals had been a set-play strike.

Goal contributions 2023/24 (all competitions)

Opposition scout: Middlesbrough

Boro were narrowly beaten at home by Aston Villa on Saturday, meaning the hosts have won only once at the Riverside since November.

Michael Carrick has a host of absentees, although he welcomed defensive midfielder Hayden Hackney, No10 Matt Crooks and joint-top marksman Emmanuel Latte Lath back at the weekend.

Leading goals contributor Sam Greenwood and new signing Finn Azaz are cup tied. Attacking midfielder Morgan Rogers is suspended, having accrued two yellow cards in this season's Carabao Cup.

Ex-Brentford winger Marcus Forss, former Blackburn anchor Darragh Lenihan and centre-back Paddy McNair are among the injured.

In addition, regular Australian pair Sam Silvera and Riley McGree are away for the Asian Cup, and first-choice goalkeeper Seny Dieng is with Senegal at the Africa Cup of Nations.

Carrick may decide to stick with Saturday’s well-structured back three. A low block was deployed against Villa, with the midfield packed and attacks focused on balls in behind for the likes of Josh Coburn and Latte Lath.

This strategy worked well until the Premier League visitors brought on their big guns and raised the pace of the game. Eventually, they exposed the cracks in Boro’s armour.

A two-leg tie, with the first at home, may embolden the former Man United schemer to be more adventurous against the Blues.

The history

Teesside fans could be forgiven for lamenting their fate when the Chelsea ball was plucked from the bowl, there being much history of significance between the pair.

Not all of it is in the Londoners’ favour, though. In May 1988, over two legs, Chelsea became the only team ever to be relegated from Division One via the play-offs at the hands of Bruce Rioch’s second-tier side.

Slow-cooked revenge came nine years later at Wembley as Ruud Gullit became the first overseas, and first black, coach to lift the FA Cup. Roberto Di Matteo famously banged in a sensational opener after just 43 seconds – then the earliest final goal at Wembley – and Eddie Newton added the second.

In the 1997/98 League Cup final, the same conclusion was reached. Di Matteo broke the deadlock again but this time Frank Sinclair, a homegrown player like Newton, was wheeling away in celebration of the second.

Two prior meetings in this competition each went the way of the hosts. In 1967 the Teessiders won 2-1 in round two, but three years later in round three the Londoners triumphed 3-2 at the Bridge.

Dave Sexton’s Blues raced into a 3-0 lead inside the opening quarter-hour through Keith Weller, Tommy Baldwin and Ian Hutchinson. Weller’s 12-second strike remains our quickest-ever goal.

Carabao Cup semi-final regulations

Progress to the Carabao Cup final on Sunday 25 February will be decided over two legs, the second of which takes place at Stamford Bridge in a fortnight.

Should the aggregate score be level at the end of ninety minutes in the second leg, a further half-hour will be played. If the two sides still can't be separated, it will come down to a penalty shoot-out.

The away goals rule does not apply in the Carabao Cup semi-finals and there is no VAR system in operation.