Garou's imitation of Blast's power can easily be surpassed by Saitama.
In previous chapters of One Punch Man, we've seen Garou mimic all of Blast's techniques and wield them at will. However, the latest chapter reveals that none of these techniques have any effect on Saitama.
1. Garou's spatial portals are swiftly kicked away by Saitama

In fact, Saitama's ability to interact with abstract entities has been demonstrated before when he entered the Phoenix Space to assist Child Emperor. And now, as Garou attempts to shift Saitama into a portal he creates, Saitama effortlessly kicks it aside, leaving Garou gaping in disbelief.
2. Saitama can also manipulate and redirect the portals

When Garou was momentarily distracted by Saitama kicking away the portal, he was punched and sent flying. Afterwards, the 'hero hunter' immediately refocused and created a new portal to launch a surprise attack on Saitama.
Interestingly, Saitama promptly seized the portal and redirected it upwards to dodge Garou's punch. He then delivered a powerful punch himself, taunting Garou to use all his martial arts techniques.
3. Garou's consecutive attacks only manage to tear Saitama's clothes

Initially, Garou opened multiple portals simultaneously and moved swiftly to disorient Saitama. He then unleashed various martial arts moves such as Roaring Aura Sky Ripping, Water Streaming Rock Smashing, Exploding Heart Release, and Whirlwind Iron Cut. He also employed his new techniques like Nuclear Fission and Gravity Knuckle.
Unfortunately, all these efforts only left Saitama's attire in tatters, while our bald hero remained unscathed.
4. Saitama's speed is so fast that he catches up to Garou at the portal

Garou has mimicked Blast's portal-opening power to maneuver freely. If under attack, Garou simply needs to open a portal and dodge.
Unfortunately, that ability proves futile when used against Saitama.
When Garou nearly got hit by Saitama's Omnidirectional Serious Punch, he opened a portal to evade. However, he was surprised when Saitama caught up to the portal and delivered another dangerous punch.
Ironically, Garou once crashed into the surface of a satellite due to his loss of sharp directional awareness and being hit by the Serious Punch.
5. Ultimately, Garou opts to 'copy' Saitama

After being overwhelmed by Saitama, Garou finally realizes that using Blast's power only gets him a one-way ticket to baldness.
Finally, Garou decides to 'cosplay' Saitama's face and devises a plan to emulate this hero's limitless power.
From here, many fans wonder if Saitama could surpass Blast's techniques if given the chance to battle the Earth's number one hero? Because Garou seems to have perfectly imitated Blast's abilities.