... or even more succinctly ...

my @rows = (
    [ qw(71 22 15 10 51) ],
    [ qw(91 82 28 11 91) ],
    [ qw(11 72 37 58 20) ],
    [ qw(21 42 63 24 16) ],
    [ qw(81 32 53 54 42) ],
);
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or, if you really need to identify each array separately ...

my @row1 = qw(71 22 15 10 51);
my @row2 = qw(91 82 28 11 91);
my @row3 = qw(11 72 37 58 20);
my @row4 = qw(21 42 63 24 16);
my @row5 = qw(81 32 53 54 42);

my @rows = ( \@row1, \@row2, \@row3, \@row4, \@row5 );
[download]