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Experimental data have provided intriguing hints for the violation of leptonflavour universality (LFU), including $B\to D^{(*)}\tau\nu/B\toD^{(*)}\ell\nu$, the anomalous magnetic moment of the muon and $b\!\to\!s\ell^+\ell^-$ with a significance of $\!>3\,\sigma$, $>\!4\,\sigma$ and$>\!5\,\sigma$, respectively. Furthermore, in a recent re-analysis of 2018Belle data, it was found that the forward-backward asymmetry ($\Delta A_{\rmFB}$) of $B \to D^{*}\mu\bar \nu$ vs $B\to D^{*}e\bar \nu$ disagrees with theSM prediction by $\approx\!\!4\,\sigma$, providing an additional sign of LFUviolation. We show that a tensor operator is necessary to significantly improvethe agreement with data in $\Delta A_{\rm FB}$ while respecting the bounds fromother $b\to c\ell\nu$ observables. Importantly, this tensor operator can onlybe induced (at tree-level within renormalizable models) by a scalar leptoquark.Furthermore, among the two possible representations, the $SU(2)_L$-singlet$S_1$ and the doublet $S_2$, which can interestingly both also account for theanomalous magnetic moment of the muon, only $S_1$ can provide a good fit. Eventhough the constraints from (differences of) other angular observables prefer asmaller value of $\Delta A_{\rm FB}$ than the current central one, thisscenario is significantly preferred (nearly $4 \sigma$) over the SM hypothesis,and is compatible with constraints such as $B\to K^*\nu\nu$ and electroweakprecision bounds. Therefore, if the $\Delta A_{\rm FB}$ anomaly is confirmed,it would provide circumstantial evidence for scalar leptoquarks and pave theway for a natural connection with all other anomalies pointing towards LFUviolation.

The Forward-Backward Asymmetry in $B\to D^{*}\ell\nu$: One more hint for Scalar Leptoquarks?