They are now knotted with the Hurricanes on 30 points - although the southern side have played one game fewer - and lie among a cluster of Kiwi sides sitting just below the Chiefs.
With the defending champions having next weekend off, the winner of the showdown in Wellington will have the chance to go top of the New Zealand conference heading into the home stretch of the competition.
If that team is to be the Highlanders, there will need to be a drastic turnaround after an uneven performance tonight. They had just returned from a South African sojourn and the fatigue of that trip began to show as the game wore on, with the Lions' slow but steady approach starting to reap rewards.
The visitors had all of the ball in the opening half but found themselves in a huge hole at the break. Aside from a pair of brief spells right after the kick-off and immediately before the halftime hooter, the Highlanders saw little possession and were left to soak up a lot of pressure.
There was a real lack of imagination from the Lions and they rarely made it over the advantage line. In contrast, the Highlanders seemed content to make their tackles and strike with real pace when they earned an opportunity.
Buckman's double emphasised that, particularly a second that came after Phil Burleigh's seemingly innocuous but brilliantly weighted clearing kick into space. The wing's speedy work looked like it would be all the Highlanders needed, and the game certainly seemed decided when Gareth Evans crossed on the stroke of halftime after excellent work from Malakai Fekitoa and Ben Smith in the build-up.
But an alteration in strategy from the South Africans, with a greater emphasis on pick-and-go, added some spice to the second half, especially after Francois de Klerk burrowed over shortly after the break.
All the work the Highlanders' defence was having to do eventually started to tell, a problem exacerbated by the sin-binning of Chris King for a stray elbow. The Highlanders were beginning to be run ragged and Lionel Mapoe's try midway through the half had the Lions threatening a late salvo.
When Armand van der Merwe converted a nice lineout movement to pull within six points, the game looked like it could be decided by the final play. And so it proved, with Jantjies unable to add the extras from Courtnall Skosan's late try.
The Highlanders did break early from the line, and the Lions argued for a retake, but Angus Gardner instead blew the final whistle. Job done but only just.
Highlanders 23 (R. Buckman 2, G. Evans tries; H. Parker con, pen, drop goal)
Lions 22 (F. de Klerk, L. Mapoe, A. van der Merwe, C. Skosan tries; M. Boshoff con)
HT: 23-0
