Despite this, by this point, Tufa Lilugu's power appeared evident, so much so that in fall 401, the new prince of Northern Liang, Juqu Mengxun, was forced to send his son Juqu Xinian (沮渠奚念) as a hostage to Tufa Lilugu to show his submission. Tufa Lilugu, however, rejected Juqu Xinian as a hostage, stating that Juqu Xinian was too young and he wanted Juqu Mengxun to send his brother Juqu Ru (沮渠挐) -- a major strategist and general for Juqu Mengxun. Juqu Mengxun initially refused—stating that he needed Juqu Ru to assist him—which drew anger from Tufa Lilugu, who sent Tufa Juyan the Marquess of Zhangsong and another brother, Tufa Wenzhi (禿髮文支) the Marquess of Xingcheng against Northern Liang and captured Juqu Mengxun's cousin Juqu Shanshan'gouzi (沮渠鄯善苟子). Juqu Mengxun made a humbler submission after that point and sent his uncle Juqu Kongzhe (沮渠孔遮) to promise to send Juqu Ru as a hostage, before Tufa Lilugu would withdraw his troops and return the people they captured. However, Tufa Lilugu himself was aware of his own power's limitations, and he also nominally submitted to Yao Xing, the emperor of Later Qin, sending tributes to Yao Xing, and in 401, when Later Qin attacked Later Liang, he ordered his troops to withdraw to yield a path for Later Qin troops.