How to strip multiple spaces to one using sed

sed on AIX is not doing what I think it should.
I'm trying to replace multiple spaces with a single space in the output of IOSTAT:

# iostat
System configuration: lcpu=4 drives=8 paths=2 vdisks=0

tty:      tin         tout    avg-cpu: % user % sys % idle % iowait
          0.2         31.8                9.7   4.9   82.9      2.5

Disks:        % tm_act     Kbps      tps    Kb_read   Kb_wrtn
hdisk9           0.2      54.2       1.1   1073456960  436765896
hdisk7           0.2      54.1       1.1   1070600212  435678280
hdisk8           0.0       0.0       0.0          0         0
hdisk6           0.0       0.0       0.0          0         0
hdisk1           0.1       6.3       0.5   63344916  112429672
hdisk0           0.1       5.0       0.2   40967838  98574444
cd0              0.0       0.0       0.0          0         0
hdiskpower1      0.2     108.3       2.3   2144057172  872444176

# iostat | grep hdisk1
hdisk1           0.1       6.3       0.5   63345700  112431123

#iostat|grep "hdisk1"|sed -e"s/[ ]*/ /g"
 h d i s k 1 0 . 1 6 . 3 0 . 5 6 3 3 4 5 8 8 0 1 1 2 4 3 2 3 5 4

sed should search & replace (s) multiple spaces (/[ ]*/) with a single space (/ /) for the entire group (/g)… but it's not only doing that… its spacing each character.

What am I doing wrong? I know its got to be something simple…
AIX 5300-06

edit: I have another computer that has 10+ hard drives. I'm using this as a parameter to another program for monitoring purposes.

The problem I ran into was that "awk '{print $5}' didn't work because I'm using $1, etc in the secondary stage and gave errors with the Print command. I was looking for a grep/sed/cut version. What seems to work is:

iostat | grep "hdisk1 " | sed -e's/  */ /g' | cut -d" " -f 5

The []s were "0 or more" when I thought they meant "just one". Removing the brackets got it working. Three very good answers really quickly make it hard to choose the "answer".