Merrell MTL Long Sky 2 Matryx Review

Merrell athletes are representing the brand with continued success these days. Once really just a hiking boot brand, the Merrell MTL Long Sky 2 Matryx proves that Merrell has what it takes to deliver results on the most demanding trails and courses. And, all that also translates into everyday athletes who want to push harder and faster into more technical terrain.

Merrell MTL Long Sky 2 Matryx Features:

• Ideal for technical trails and racing
• Vibram MegaGrip outsoles with 5mm lugs
• Low drop (4mm) and stack height (23.5-19.5mm)
• Durable Kevlar-infused Matryx uppers
• FloatPro foam midsole
• Weight: 10 oz each (11.5, actual)
• MSRP: $170

Speed… my name is speed

Merrell’s trail running game is getting better and better and the MTL Long Sky 2 is a great example of why that’s the case. These are not your daddy’s Merrell shoes — you know the ones he wore hiking and to work back in the 1990’s. No, the MTL Long Sky 2 is a technical trail runner that’s made for speed across the most technical terrain you can find. While I’m not racing along the most craggy ridge lines, I’m adeptly pushing myself on the dry, loose trails here along the Wasatch Front in these zippy shoes.

First off, the construction is obviously lightweight and fast. Going from shoes with 30mm+ stack height (La Sportiva Prodigio Max) to these has been an adjustment. And, that close-to-terra feel has definitely relegated the MTL Long Sky 2’s  to trail-only duty. But, don’t let my old bones sway you from some road approaches in a pinch.

It doesn’t take an astute eye to see that these shoes are built for racing. At a mere 10 oz., they are the lightest and most airy shoes I’ve tested in a long time (since the Hoka Zinal 2). Still, they aren’t ultralight, just light. Matryx mesh is an incredible material for trail shoes with its lightweight, super-airy, tough and supportive character. Merrell really optimized every bit of these shoes for their trail running athletes, with Frédéric Tranchand wearing them to win the 2025 Trail World Championships.

You can never go wrong with a standard lacing system and these are easily-cinched. They provide a glove-like fit, with a thin, breathable tongue. The lightweight uppers and minimal tongue padding do require a little thicker sock to prevent the upper lacing from digging into my feet. Added sock thickness adds a touch more cushion and fills the uppers perfectly. Even with this, I did have to be careful not to pull the knot too tight. it became a balancing act that took some time to get right, but now I’m just used to not cinching them down as I would other shoes.

Once laced up, I would definitely use the lace loop for added lace security. These meaty lugs do have a tendency to grab onto things and heaven forbid I catch a lace loop while running. The Matryx uppers offer excellent stability and structure. My feet have flat arches and I do typically appreciate a little more instep support, but I haven’t noticed any adverse issues here.

You’ll notice that there is minimal toe protection around the forefoot and toe tread — just enough to minimize any adverse effects of rock punting. The cuffs are minimalistic, like everything else. With that, I did find that my foot shape did cause some gaps in the cuffs, which did allow more trail scree than I see with other shoes. I’m surprised there isn’t a heel loop for easier entry, but the laces are easily-expanded for foot entry. This lightweight design makes for imperceptible swing weight. I don’t feel them at all and each step feels unweighted.

The 4mm, well-spaced Vibram lugs offer butt-kicking traction on all terrain. Uphill, downhill, off-camber and everything in-between has always been met with confidence. Toe-off is outstanding and the shoes just propel me forward with every push. On smooth and fast trails, rocky ascents and chunky descents, the tread pattern and stickiness is superb. Going fast is what these shoes are meant to do, but there is no lack of traction anywhere. While the treads to grip and propel me forward, the shoe itself doesn’t offer much in the way off immediate, forward-propulsion like other shoes do.

Stability is a strong suit of the MTL Long Sky 2’s as well. The trapezoidal midsoles and Matryx uppers work together to cradle my feet and provide excellent stability on uphill, downhill and off-camber trails. That low-profile design and excellent midsole stability really delivers. Trail feel is the perfect balance between protection and grounded. I can detect every nuance while still not worrying about sharp rocks on each step.

Breathability is outstanding — so much so that I’ve been grateful for some thicker socks over the past few weeks. Airflow just passes right through the uppers and I’ve never once felt like I’ve overwhelmed these shoes. They simply breathe and breathe well. I would absolutely feel confident running in the mid-day sun with these.

Fit: I’m wearing a size 11.5, which is my usual size across every other brand I’ve worn. 

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The Bottom Line

9.0 Long Sky Racers

The Merrell MTL Long Sky 2 Matryx is a lightweight, race-focused trail shoe built for speed on technical terrain, with airy yet durable Matryx uppers and Vibram MegaGrip lugs that bite confidently into everything from loose dirt to rocky climbs. With a low stack and 4mm drop, I’m getting excellent trail feel and stability, though comfort and support remain minimal — these are purpose-built for fast, technical trails, not plush cruising. The fit is secure once dialed in, but the thin tongue and upper may require thicker socks to prevent lace pressure. For runners who prioritize precision, agility, and breathable performance, these are sharp, capable shoes that reward an aggressive running style.

The Good:

1. Outstanding breathability
2. Matryx uppers take a beating and keep on ticking
3. Surprisingly-stable for such a minimalist shoe
4. Traction aplenty — everywhere
5. Lightweight feel that never weighs me down
6. Have become more and more awesome as the miles have increased

The Bad:

1. Cuffs allow more trail scree than other shoes
2. Thin tongue requires careful lacing
3. Shoe design doesn’t immediately propel me forward with each step

• Lacing and Fit 9

• Support 8

• Cushioning 8

• Traction 10

• Trail Feel 9

• Stride 9

• Breathability 10