up against it
squeeze
dire straits
tight spot
strait
between a rock and a hard place
left in the lurch
spot
jam
knot
jackpot
on the spot
in trouble
struggle bus
tough going
difficult situation
how do you do
hot potato
hard case
in the lurch
in a corner
toughly
against the collar
hard-pressed
bitch and a half
piledriver
ectopic
superdifficult
bunker
hard
on the edge
mountainous
uphill
murderous
fiendish
clutch
harder than Chinese math
hard as Chinese algebra
taxing
get into trouble
shove
overchallenge
toughish
semitough
flounder
run for one's money
postdoc
at loose ends
lob
strainedly