Puzzle 14

Opportunity for a tennis player to dispute a call

Give up something valuable; offering to a deity

Symbolised by an A in tennis, happens after 40-40

Business show with exhibition stalls

Singer-songwriter of Song for Guy

Multiple by four

Denying a place within, cutting someone out

Russian city formerly named Stalingrad

Unexpectedly reverse one's previous opinion

Roman emperor began construction of the Colosseum