Hines means Swansea are full of beans after own goal halts Boro run

Swansea celebrated reaching the semi-finals of the League Cup for the first time but it was with a limp rather than a strut against gutsy Middlesbrough. For an hour, it was the Championship team who provided the touch of class until a crucial substitution and an own goal turned this quarter-final tie on its head.

Ki Sung-Yueng stepped off the bench to spark Swansea into life as their opponents tired before an own goal nine minutes from time by Seb Hines left the Welsh club three games from Europe. Before that, Swansea lacked composure, style or class, attributes that defined Michael Laudrup as a player and, until last night, his team.

Goals came easy in previous rounds for Swansea, scoring three in each of their previous three games, but gone was their swagger as Saturday's home defeat to Norwich looked to have knocked their confidence.

Securing Premier League football for next season may well be the priority for both these clubs, but events 24 hours earlier at Valley Parade galvanised this tie. Bradford's win over Arsenal served as inspiration to both. Swansea, making their first appearance at this stage of the League Cup, usurped Cardiff City in reaching the Premier League, though were eager to emulate their arch rivals' Wembley appearance last season in this competition.

Manager Michael Laudrup named a strong team bolstered by the return to fitness of midfield linchpin Leon Britton, but early on they lacked their usual fluidity. In contrast, Middlesbrough, third in the Championship, won this competition in 2004, still the only silverware in their 136-year history. They started brightly with a sixth semi-final appearance at stake.

They were certainly not over-awed at the Liberty Stadium. Tony Mowbray's side, cajoled by 600 travelling fans transported by the tournament sponsors, are adept at life on the road in this competition having been drawn away for the 12th tie in succession. Captain Grant Leadbitter was denied in the opening minute by a crucial Chico Flores intervention.

Lukas Jutkiewicz and Nicky Bailey forced saves from Gerhard Tremmel as Middlesbrough out-passed and frustrated Swansea. Jutkiewicz and Faris Haroun set up Leadbitter for the best chance of a scrappy half but Tremmel was again alert.

Swansea were lacklustre and their only chance of note in the first half was Nathan Dyer's deflected effort after they had finally got the ball wide and in space to Ben Davies. Laudrup brought on Luke Moore and he made his presence felt in a tussle with Andre Bikey. However it was the introduction Ki on 65 minutes that brought Swansea to life.

The South Korean international breached the gap between the midfield intricacy and the attackers, driving at Middlesbrough and putting them onto the back foot. That released Dyer and when he was felled by Nicky Bailey, Jonathan de Guzman saw his curling free-kick athletically tipped onto the crossbar by Jason Steele.

However the tide had turned and suddenly Swansea besieged the visitors' box. Hines twice intervened, first escaping a penalty shout for his challenge on Ki and then as Michu was set to pull the trigger.

Yet by a cruel twist of fate, it was the centre-back who proved decisive, leaping under pressure from Gary Monk for De Guzman's corner, only to direct the ball into his own goal. At this stage, Swansea will not care how the goals go in.