The 20-year-old was not part of Bielsa's squad at Tottenham Hotspur Stadium on Sunday, the head coach deciding to take different youngsters as his potential substitutes for wide positions.
"I decided for [Liam] McCarron and [Stuart] McKinstry," said Bielsa when asked if Summerville was injured.
Leeds' travelling party in London last weekend included 15-year-old Archie Gray who has stepped up into the Under 23s this season and played in an 'Under 21s' side in the EFL Trophy.
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Summerville has made four appearances in the Premier League this season as a substitute, having taken Helder Costa' s place in the pecking order among Bielsa's wingers. He has also played seven times in Premier League 2 for Mark Jackson's side.
The former Feyenoord prospect represented Netherlands Under 21s twice during the international break, making his first start and scoring against Gibraltar.