The Juventus striker has been in fine form for the Italian champions this season, scoring 11 goals in all competitions - including two in his last two.
And Morata's rise looks set to continue on the international stage this week, with the 22-year-old likely to lead the line for his country in Seville as regular starter Costa has a hamstring injury.
Del Bosque will hope Morata can transfer his club form into the international arena, with Spain sitting second in Group C - three points adrift of leaders Slovakia and level with Ukraine.
Spain have lost three of their six matches since their ignominious World Cup exit, but their home record in competitive games remains impressive.
Avoiding defeat against Ukraine would extend their unbeaten record on home soil to 30 matches, with their last competitive defeat in Spain coming against Greece way back in June 2003.
Ukraine should not be underestimated, though, with Mikhail Formenko's side having only lost three of their last 25 fixtures.
Defensive solidity has been one of the main reasons behind Ukraine's strong form, with Formenko's men conceding just five goals in that time - three of which came in a World Cup qualifier to France in November 2013.
Like Del Bosque with Costa, Formenko has had to deal with a late withdrawal from his squad after Sergiy Sydorchuk suffered an injury during Dynamo Kyiv's UEFA Europa League clash with Everton.
Dynamo have eight other players in the squad travelling to Spain, with forward Andriy Yarmolenko looking to add the three goals he has already scored in qualifying.
"We prepare in exactly the same way for every opponent," the 25-year-old told UEFA.com. "We'll dedicate an hour to watching them.
"It was the same for San Marino, we watched four or five of their games, so for Spain we'll watch even more.
"We know Spain very well and how difficult it will be against them."
