‘Swifty’ has a visible size difference over the two-time world title challenger at the First Direct Arena in Leeds and from the off it seemed to be just a matter of time before his power told.
Despite a couple of rounds where Smith looked solely for the knockout, the 28 year-old got his tactics right in the end as Munoz failed to come out for the ninth round following a one-sided contest.
In the headlining fight, Josh Warrington remained undefeated with a wide points win over Martin Lindsay to pick up the vacant British featherweight belt to add to his Commonwealth version.
Now 18-0, Warrington, 23, built up a commanding lead in front of his home fans to eventually see out the fight 119-110 on all three of the judges scorecards.
Also on the bill, Gavin McDonnell kept hold of his British super-bantamweight by the narrowest of margins following a high-energy twelve-rounder with a game Josh Wale.
The Doncaster man seemed to fend off Wale with the cleaner work in the closer rounds, although after a pulsating contest, the judges failed to split them.
Wale put in the performance of his life to push the champion hard until the final bell, but scores of 115-114, 114-115 and 114-114 thwarted his attempts to finally clinch a Lonsdale belt.
Having won their first meeting last year, McDonnell was keen to emphasize that we would be willing to engage in a third fight with Wale, something which nobody would argue with at the final bell.
Kal Yafai proved way too hot for Yaqub Kareem to handle as the big-hitting super-flyweight claimed the vacant Commonwealth title with a crushing third round knockout.
The 24 year-old produced some hurtful shots from the very first minute and had Kareem in trouble for the duration until a sweet body shot put the Nigerian down for the count.
Brother Gamal Yafai made a successful pro debut at bantamweight with a punishing win over the stunned Ricky Leach. The younger sibling came out swinging from the off and Leach had no answer to the onslaught forcing the referee to end his troubles before the end of the opening session.
Earlier, cruiserweight Simon Vallily dominated Moses Matovu on the journeyman’s 50th pro outing – winning every round on his way to a 40-36 triumph. Vallily, 28, is now 4-0 since entering the paid ranks in March last year, but is yet to have an early night despite not losing a single round.
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