The two Smiths, Aaron and Ben, battled to get the Highlanders over the gainline, but they were hampered by the first-half injury to wing Patrick Osborne. With only two backs on the reserves bench, the loss of their strike weapon was a big one.
The Lions loose trio, led by skipper Jaco Kriel in the absence of Warren Whiteley, dominated their opposites. New All Black Elliot Dixon, one the heroes for the Highlanders in last year's final at the Cake Tin, dropped the ball over the line in the first half after Waisake Naholo and Malakai Fekitoa fashioned something out of nothing, a mistake typical of the Highlanders' performance.
It meant the Lions took a 17-6 halftime lead, and while the Highlanders are as good as anyone in this competition at chasing a match, this was a bridge too far following their gruelling schedule in recent weeks which has seen them travel from South Africa to Argentina to New Zealand, Australia and back to South Africa again.
The final margin wasn't a huge one, and the Lions only outscored the Highlanders five tries to four, but like in their quarter-final win over the Crusaders last weekend, they were in control from the start and never relinquished their grip on the match. Coach Jamie Joseph will now leave the franchise to coach Japan but despite his disappointment he should be proud of the way his team performed as defending champions this year.
The Lions are a rarity for a South African team in that they combine a strong set piece with a talented backline which plays with flair and ambition. After beating the Chiefs in Hamilton and exceeding most expectations this year, the former easy-beats will travel with confidence.
"They fully deserved the win," Ben Smith said afterwards. "The kind of rugby they've been playing has been unreal. We wish them all the best for the final, it's going to be an unreal final.
"We couldn't put pressure on the Lions or execute... we will learn a wee bit from coming here - it's a tough place to play."
Lions 42 (Elton Jantjies, Rohan Janse van Rensburg, Courtnall Skosan, Jaco Kriel, Lourens Erasmus tries; Jantjies 4 cons, 3 pens)
Highlanders 30 (Matt Faddes, Lima Sopoaga, Waisake Naholo, Joe Wheeler tries; Lima Sopoaga 2 pens, 2 cons)
Halftime: 17-6