diff --git a/src/test/perl/PostgreSQL/Test/BackgroundPsql.pm b/src/test/perl/PostgreSQL/Test/BackgroundPsql.pm
index a552132484e..59b91358656 100644
--- a/src/test/perl/PostgreSQL/Test/BackgroundPsql.pm
+++ b/src/test/perl/PostgreSQL/Test/BackgroundPsql.pm
@@ -152,11 +152,11 @@ sub wait_connect
 	#
 	# See query() for details about why/how the banner is used.
 	my $banner = "background_psql: ready";
-	my $banner_match = qr/(^|\n)$banner\r?\n/;
-	$self->{stdin} .= "\\echo $banner\n\\warn $banner\n";
+	my $banner_match = qr/$banner\r?\n/;
+	$self->{stdin} .= "\\echo '$banner'\n\\warn '$banner'\n";
 	$self->{run}->pump()
 	  until ($self->{stdout} =~ /$banner_match/
-		  && $self->{stderr} =~ /$banner\r?\n/)
+		  && $self->{stderr} =~ /$banner_match/)
 	  || $self->{timeout}->is_expired;
 
 	note "connect output:\n",
@@ -256,22 +256,17 @@ sub query
 	# stderr (or vice versa), even if psql printed them in the opposite
 	# order. We therefore wait on both.
 	#
-	# We need to match for the newline, because we try to remove it below, and
-	# it's possible to consume just the input *without* the newline. In
-	# interactive psql we emit \r\n, so we need to allow for that. Also need
-	# to be careful that we don't e.g. match the echoed \echo command, rather
-	# than its output.
+	# In interactive psql we emit \r\n, so we need to allow for that.
+	# Also, include quotes around the banner string in the \echo and \warn
+	# commands, not because the string needs quoting but so that $banner_match
+	# can't match readline's echoing of these commands.
 	my $banner = "background_psql: QUERY_SEPARATOR $query_cnt:";
-	my $banner_match = qr/(^|\n)$banner\r?\n/;
-	$self->{stdin} .= "$query\n;\n\\echo $banner\n\\warn $banner\n";
-	pump_until(
-		$self->{run}, $self->{timeout},
-		\$self->{stdout}, qr/$banner_match/);
-	pump_until(
-		$self->{run}, $self->{timeout},
-		\$self->{stderr}, qr/$banner_match/);
-
-	die "psql query timed out" if $self->{timeout}->is_expired;
+	my $banner_match = qr/$banner\r?\n/;
+	$self->{stdin} .= "$query\n;\n\\echo '$banner'\n\\warn '$banner'\n";
+	$self->{run}->pump()
+	  until ($self->{stdout} =~ /$banner_match/
+		  && $self->{stderr} =~ /$banner_match/)
+	  || $self->{timeout}->is_expired;
 
 	note "results query $query_cnt:\n",
 	  explain {
@@ -279,9 +274,12 @@ sub query
 		stderr => $self->{stderr},
 	  };
 
-	# Remove banner from stdout and stderr, our caller doesn't care.  The
-	# first newline is optional, as there would not be one if consuming an
-	# empty query result.
+	die "psql query timed out" if $self->{timeout}->is_expired;
+
+	# Remove banner from stdout and stderr, our caller doesn't want it.
+	# Also remove the query output's trailing newline, if present (there
+	# would not be one if consuming an empty query result).
+	$banner_match = qr/\r?\n?$banner\r?\n/;
 	$output = $self->{stdout};
 	$output =~ s/$banner_match//;
 	$self->{stderr} =~ s/$banner_match//;